Tire Pressure Systems – Confidence Report 

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Tire Pressure Systems

Report of a study conducted by the North American Council for Freight Efficiency

on the Confidence of Adopting Tire Pressure Systems

August 15, 2013

© 2013 North American Council for Freight Efficiency. All rights reserved.

The contents of this document are provided for informational purposes only and do not 

constitute an endorsement of any product, service, industry practice, service provider, 

manufacturer, or manufacturing process. Nothing contained herein is intended to constitute 

legal, tax, or accounting advice, and NACFE assumes no liability for use of the report contents. 

No portion of this report or accompanying materials may be copied, reproduced or distributed 

in any manner without express attribution to the North American Council for Freight Efficiency.
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Acknowledgements

Study Team:

Janelle Liechty, NACFE Program Analyst

Susan Nelson, Blue Stripe Scientific LLC, NACFE Program Manager

Mike Roeth, NACFE Executive Director

Suzanne Slick, NACFE Senior Researcher

External Advisor on Fleet Operations: Gary Cullen, Cullen Consulting Concepts LLC 

Study Sponsors:

Aperia Technologies Inc.

Bendix Commercial Vehicle Systems LLC

Doran Manufacturing LLC

Frito-Lay North America Inc.

Goodyear Tire & Rubber Company

Michelin North America Inc.

P.S.I. Pressure Systems International

NACFE Technical Advisory Committee:

Tim Dzojko, Air Products

Allen Nielsen, CR England

Mike O’Connell, Frito Lay

Scott Perry, Ryder

Steve Phillips, Werner Enterprises

Yves Provencher, FPInnovations 

Mike Roeth, NACFE Executive Director

Dale Spencer, UPS

Bruce Stockton, Stockton Solutions
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Table of Contents

List of Terms and Acronyms................................................................................................................5

List of Exhibits....................................................................................................................................6

Executive Summary............................................................................................................................7

1.0 Introduction and Background .....................................................................................................11

1.1 Rationale for Study of Tire Pressure Systems................................................................................... 11

1.2 Expected Performance Benefits and Industry Stakes....................................................................... 12

1.3 Regulatory Perspectives for Tire Pressure Systems in Commercial Vehicle Applications................ 15

1.4 Study Objectives............................................................................................................................... 17

2.0 Study Approach..........................................................................................................................17

3.0 Description of Currently Available Tire Pressure Systems for Commercial Vehicles.......................19

3.1 Tire Pressure Monitoring Systems (TPMS)....................................................................................... 21

3.1.1 Non-Transmitting Wheel-End Sensors...................................................................................... 22

3.1.2 Transmitting Wheel-End Sensors.............................................................................................. 22

3.1.2.1 External Valve Stem Mounted/External Wheel Mounted 

Tire Pressure Monitors ..................................................................................................... 22

3.1.2.2 Internal Valve Stem Mounted/Internal Wheel Mounted/Tire Casing

Mounted TPMS ................................................................................................................. 27

3.1.3 Pressure Sensing Mats .............................................................................................................. 31

3.1.4 Manual Tire Pressure Check Procedures in Fleets.................................................................... 32

3.2 Dual Tire Pressure Equalizer Systems............................................................................................... 33

3.3 Automatic Tire Inflation Systems (ATIS)........................................................................................... 34

3.3.1 ATIS Type 1 – Vehicle Tank Air Source ...................................................................................... 36

3.3.2 ATIS Type 2 – Direct Atmospheric Air Source with Self-Contained Pump ................................ 41

3.4 Central Tire Inflation Systems (CTIS) ................................................................................................ 45

3.5 Passive Pressure Containment Approaches..................................................................................... 45

3.5.1 Nitrogen Inflation...................................................................................................................... 45

3.5.2 Tires with Built-in Sealant Layer................................................................................................ 46

3.5.3 Aftermarket Sealants ................................................................................................................ 47

4.0 Original Equipment Manufacturers’ Perspectives on Tire Pressure System Integration .................48

4.1 Trailer OEMs..................................................................................................................................... 48

4.2 Tractor OEMs.................................................................................................................................... 49

5.0 Summary of Fleet Perspectives and Experiences with Current Tire Pressure Systems....................49

6.0 Tools – Technology Decision Matrix and Payback Calculator........................................................53

6.1 Technology Decision Matrix ............................................................................................................. 53

6.2 Payback Calculator............................................................................................................................ 54

7.0 Fleet Case Studies.......................................................................................................................56

7.1 Case Study 1: For-Hire Fleet Adopts ATIS for Trailer........................................................................ 56

7.2 Case Study 2: Private Carrier Adopts TPMS for Tractor and Trailer................................................. 59

8.0 Perspectives for Future Tire Pressure Systems.............................................................................61
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Table of Contents (continued)

9.0 Study Conclusions ......................................................................................................................64

References.......................................................................................................................................65

Appendix A: Product Summary Sheets for Selected Tire Pressure Technology Categories...................68

Appendix B: Expanded List of Tire Pressure Systems Suppliers ..........................................................83

Appendix C: Contributing Systems Suppliers.....................................................................................88
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List of Terms and Acronyms

ACT – Americas Commercial Transportation Research Co. LLC

ATA – American Trucking Associations

ATIS – Automatic Tire Inflation System

ATRI – American Transportation Research Institute

BASIC – Behavior Analysis and Safety Improvement Category (part of CSA program)

CAN – controller area network

CFM – cubic feet per minute, measure of fluid flow rate

CIP – cold inflation pressure

CPM – cost per mile

CSA – FMCSA Compliance, Safety, Accountability program

CTIS – Central Tire Inflation System

ECU – electronic control unit

EPA – Environmental Protection Agency

FMCSA – Federal Motor Carrier Safety Administration

FMVSS – Federal Motor Vehicle Safety Standard

GPO – Government Printing Office

GVWR – gross vehicle weight rating

LTL – For-hire less-than-truckload carrier

NACFE – North American Council for Freight Efficiency

NHTSA – National Highway Traffic Safety Administration

NPTC – National Private Truck Council

NTSB – National Transportation Safety Board

OEM – original equipment manufacturer

PSI – pounds per square inch, measure of pressure

RF – radio frequency

ROI – return on investment, reported in months needed to recover initial cost of acquisition

SAE – SAE International, formerly Society of Automotive Engineers

SMS – Safety Measurement System for CSA program online reporting

TL – For-hire truckload carrier

TMC – Technology & Maintenance Council

TPMS – Tire Pressure Monitoring System
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List of Exhibits

Exhibit 1.1 Summary of Tire Pressure System Adoption Rates from NACFE 2013 Benchmark Study

Exhibit 1.2 Summary of Federal Legislation Related to Tire Pressure Systems in Commercial Vehicles

Exhibit 3.1 Classification of Tire Pressure System Technologies

Exhibit 3.2 External Valve Stem/External Wheel Mounted TPMS (with Transceiver/Repeater)

Exhibit 3.3 External Valve Stem/External Wheel Mounted TPMS (direct transmission to in-cab unit)

Exhibit 3.4 Potential Risks Associated with Use of External Valve Stem/External Wheel Mounted TPMS

Exhibit 3.5 Internal Valve Stem/Internal Wheel Mounted/Internal Tire Mounted TPMS

Exhibit 3.6 Internal Valve Stem/Internal Wheel Mounted/Internal Tire Mounted TPMS: 

Tractor-Trailer Configuration

Exhibit 3.7 Potential Risks Associated with Use of Internal Valve Stem/Internal Wheel Mounted/

Internal Tire Casing Mounted TPMS

Exhibit 3.8 Configuration of ATIS Type 1 – Vehicle Tank Air Source

Exhibit 3.9 Potential Risks Associated with Use of ATIS Type 1 - Vehicle Tank Air Source

Exhibit 3.10 Potential Risks Associated with Use of ATIS Type 2A – Direct Atmospheric Air Source

Exhibit 5.1 Historical Rates of For-Hire Truckload Carrier Driver Turnover 2005-2012

Exhibit 5.2 Historical Rates of Private Carrier Driver Turnover 2005-2012

Exhibit 6.1 NACFE Tire Pressure System Technology Decision Matrix

Exhibit 6.2 NACFE Tire Pressure Payback Calculator – Owner/Operator

Exhibit 7.1 NACFE Tire Pressure Payback Calculator – For-Hire Fleet with Trailer ATIS

Exhibit 7.2 NACFE Tire Pressure Payback Calculator – Private Fleet with TPMS on Tractor and Trailer
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Executive Summary

The North American Council for Freight Efficiency (NACFE www.nacfe.org) is a nonprofit organization 

dedicated to doubling the freight efficiency of North American goods movement. NACFE operates as a 

nonprofit with the objective of providing independent and unbiased research to support the 

transformation of the transportation industry. Information is a critical component of decision-making

and NACFE is proving to help the industry with real-world data for fleets and manufacturers to take 

action to improve their operations and products. This specific study highlights successes achieved by 

innovative fleets through the use of tire pressure technologies supplied by leading manufacturers, and 

provides a platform for those fleets to share their experiences in order to encourage quicker adoption of

tire pressure systems across the transport industry. 

For the purposes of this study, tire pressure systems refer to on-vehicle and/or in-tire products and 

methods to assess and manage proper tire inflation on commercial trucks. On close examination, this 

industry was seen to be extremely diverse, with many players and a wide range of available products

aimed at helping fleets measure and control the inflation pressure of their tires. There was also user 

uncertainty regarding the capabilities of each technology and the ability of the various tire pressure 

systems to meet the fleet’s specific needs. In this context, the first task of the project team was to 

identify and categorize the different types of systems currently available in the market. The result of 

this effort is shown in the following chart, and each technology is discussed in detail in Chapter 3.
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Even though the categories shown above are all grouped under the umbrella of “tire pressure systems”, 

not every technology can address every type of tire inflation problem. Nor does every technology 

provide the same level of information to the user about the pressure condition of a specific tire. 

To help clarify performance capabilities by technology, the second task of the team was to identify a 

hierarchy of tire air losses, which could then be used to differentiate between commercial systems and

also used to match fleet needs to product type. Excluding catastrophic air loss, which is judged to be 

outside the scope of the study, the general classes of tire air losses to be considered in the project are 

described below, listed in order of increasing severity.

 Natural air diffusion or permeation through the casing.

 Air seepage due to improper bead seating, a malfunctioning valve, or leaking valve seal.

 Slow to moderate air leaks primarily due to small punctures.

 Rapid air loss due to more significant punctures, but not including sudden, catastrophic air 

losses.

The approximate rate of air loss associated with each type of leak is presented in the report, based on 

documented natural air loss rates in tires as well as the reported pressure-loss detection capabilities of 

the various monitoring systems and, in the case of automatic inflation technologies, the air flow capacity

which can be sustained by the system to overcome continuing inflation gas loss. It is hoped that future 

industry discussions will refine these categories of air loss in tires and the air flow rates associated with 

each leakage type. 

Tire pressure systems should be looked at in light of their capacity to address the different types of air 

loss in tires. For example, tire pressure monitoring systems (TPMS) cannot add air to an underinflated 

tire, but these systems provide the most extensive and flexible reporting of actual tire condition to the

user, and are able to warn users about all the types of air losses that may be occurring. An automatic 

tire inflation system (ATIS) can restore air to tires, with different systems capable of handling different 

levels of underinflation, but such systems usually do not report the actual inflation pressure in any given 

tire. A less obvious example is the case of aftermarket sealants, which attempt to reduce the effect of 

air loss due to both air permeation and small punctures. Each system presents its own set of advantages 

and potential drawbacks. It is important for users to identify the type of tire inflation concern that has 

the most impact for their particular operations, and then choose the tire pressure technology that best 

tackles that type of problem.

The NACFE project team reviewed a number of previously published studies from FMCSA and NHTSA on 

tire pressure system performance. These were studies comparing mainly dual tire pressure equalizers,

sensor-based TPMS, and ATIS using air supplied by vehicle air tanks (Type 1). Both TPMS and ATIS were 

then evaluated in real-world field operational tests in fleets by FMCSA. The NACFE team was not able to 

identify any published or proprietary studies that compared the relative performance or reliability of any 

of the other technology categories/subcategories – for instance, pressure sensing mats versus TPMS, or 

aftermarket sealants versus dual tire equalizers. Thus, due to the wide variety of product attributes, 

functions and capabilities of each technology, and given that product testing was outside the scope of 

the NACFE project, there is no basis for ranking or rating the entire body of tire pressure technology 

categories. Future projects could focus on comparison of products within a given technology sub-
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category, that is, those products intended to yield the same functionality at generally similar price 

points.

The FMCSA and NHTSA evaluations of dual tire pressure equalizers, sensor-based TPMS, and ATIS Type 1 

demonstrated that all products function largely as designed by the manufacturers. Products that did not 

function well initially were significantly upgraded during the course of those studies, or are no longer on 

the market. Generally speaking, these three categories of today’s tire pressure products are expected to 

perform well in the field based on these results.

In contrast, NACFE project team Internet surveys and interviews with fleets, who generally expressed 

positive opinions towards tire pressure systems, indicated somewhat mixed feelings about system 

reliability and payback. Certain fleets had favorable results with their adopted technologies, while other 

fleets had tried and abandoned the same technology. 

It is the feeling of the NACFE team that this gap between the results of controlled testing versus some 

fleet experiences can perhaps be explained by how well a fleet has matched their needs to the actual 

capabilities of a specific tire pressure system, and the amount of preparation a fleet is willing to go 

through to ensure successful adoption of a new technology. For example, 100% of the fleets surveyed 

by NACFE indicated that they had updated their routine or preventive maintenance plans to include 

inspections of their tire pressure systems, and 2/3rds had added a training program for their 

maintenance teams on the use of the equipment. Factors contributing to a satisfactory operation of tire 

pressure systems include:

 The precondition for fleets to match their needs with the specific capabilities of the various

tire pressure systems when making purchase decisions.

 The importance of user readiness, in terms of personnel training and preparation of internal 

operating procedures around new tire pressure systems, to ensure successful deployment in 

the fleet.

 The need for the functionality of tire pressure systems (alerts, warnings, data reporting) to 

integrate relatively seamlessly into normal, day-to-day fleet operations without requiring 

significant system oversight or maintenance by the fleet.

NACFE has put together the following tools and information in the report to help support the 

development of a good decision-making process for the purchase of various tire pressure technologies.

1. Risks of Technology Adoption. For sensor-based TPMS and ATIS, NACFE has created a table

of potential operational risks associated with the products. This should not discourage any 

user from adopting a particular product, but instead is intended to be used in fleet internal 

discussions of their readiness to accept a new technology. High-level risks are summarized 

for the other categories of products. These tables are included in Chapter 3.

2. Tire Pressure Technology Decision Matrix. This tool identifies the major attributes of the 

various tire pressure technology types in a single chart. End users, tire pressure systems 

manufacturers, tractor and trailer builders and others can select specific systems of interest 

and compare the characteristics of the various technologies. A description of this matrix is 

found in Chapter 6, and the tool will ultimately be available from the NACFE web site. This 
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tool is meant to condense the immense amount of information obtained during this study 

effort into a single matrix that can assist in the choice of various technology types for

specific fleet operations.

3. Payback Calculator. The NACFE calculator uses data from various published sources, 

including the Federal Motor Carrier Safety Administration, the Technology and Maintenance 

Council, tire manufacturers, fleets, the tire pressure systems suppliers, tractor and trailer 

manufacturers and others. It calculates a simple payback in terms of roadside breakdowns, 

tire wear and fuel economy cost reductions given the use of the vehicles and data supplied 

by the fleet. Users may evaluate tractor-only, trailer-only, and tractor-plus-trailer fitments. It 

is a balanced and straightforward tool to be used by stakeholders in the industry to show 

the general economics for tire pressure system adoption. The payback calculator tool is

described in Chapter 6, and will also be available from the NACFE web site. Although the 

tool is aimed at TPMS and ATIS technologies, a fleet with appropriate information could 

conceivably apply the tool to any tire pressure system or methodology.

4. Case Studies. Based on fleet interviews, representative case studies were developed for a 

For-Hire fleet installing trailer ATIS (Type 1) and a Private Carrier adopting TPMS on both

tractors and trailers. Time to achieve payback using the NACFE calculator is in the range of 

9-14 months for these two case studies.

5. Product Summary Sheets. Product summary sheets were developed for seven TPMS and 

five ATIS products and are included in Appendix A of this report. Each page contains a brief 

description of the system, product details such as alert levels, procurement options, and

distinctive features. The appearance, or lack thereof, of an individual commercial product in 

this Appendix is not an indication of its performance, quality, functionality, or of any 

endorsement or recommendation by NACFE. NACFE does not endorse products or 

manufacturers. Products were chosen based on several factors: level of reported use by 

fleets and OEMs; the extent to which a particular product is characteristic of a category of 

tire pressure systems; and whether the product offers one or more unique features in its 

configuration, functionality, or technical approach. 

6. Expanded List of Products and Systems Suppliers. An expanded list of commercially 

available tire pressure systems by category, including primary attributes and company 

contact information, is included in Appendix B. Five tire pressure technology categories and 

over 30 products are cited in this table. This list is not considered to be all-inclusive, given 

the potential for rapid turnover of products in the market. 

As adoption of tire pressure technologies expands in the industry, it is expected that creative solutions

will continue to be developed with improved performance, even better reliability, greater functionality, 

overall lower cost, and probably greater standardization, and will help sustain improvements in the 

efficiency and reliability of North American commercial freight transport.
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Chapter 1.0 Introduction and Background

The North American Council for Freight Efficiency (NACFE or “the Council”) was created in 2009 with the 

objective of supporting the transportation industry in the adoption of technologies that could deliver

significant improvements in fuel savings and fleet operations. In support of that goal, in 2012 the Council 

embarked on a program to look at existing commercial product offerings for certain selected 

technologies. The Tire Pressure Systems Project represents NACFE’s first study report to be released

under this new program.

1.1 Rationale for Study of Tire Pressure Systems

In 2011, the Council published its first benchmark report on the penetration of approximately 60 fuel 

saving products or practices across ten commercial truck fleets. The information was updated in 2012, 

and released in a second report in March 2013 (NACFE, 2013). Included in the report was the adoption 

rate of tire pressure monitoring systems (TPMS) for tractor and for trailer, as well as automatic tire 

inflation systems (ATIS) for trailer, and the use of nitrogen inflation. Dual tire equalizers, central tire 

inflation systems (CTIS), tires with built-in sealant layers, aftermarket sealants, and garage floormounted tire pressure sensing mats were not included in the benchmark study. 

The benchmark study reflects equipment that was purchased as part of new vehicle procurement, and 

does not include aftermarket installation of the technology. To date, ATIS for trailer applications has 

seen the greatest adoption rate among the fleets included in the survey. The 2010-2012 data suggests 

that adoption of TPMS and ATIS appears to have leveled off, but this is likely due to the stabilization of 

tire inflation practices among the specific fleets included in the benchmark study.

Exhibit 1.1 Summary of Tire Pressure System Adoption Rates from NACFE 2013 Benchmark Study
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After a review of the study results, the NACFE Board of Directors and Technical Advisory Committee 

approved a more detailed study with specific focus on tire pressure systems, to improve the level of 

information available on existing commercial systems and to identify fleet practices that would increase 

the success of tire pressure system implementation.

1.2 Expected Performance Benefits and Industry Stakes

All industry stakeholders, including fleets, technical trade associations, tire pressure systems suppliers, 

original equipment manufacturers, tire manufacturers, and government administrators, agree on the 

importance of proper tire inflation to ensure safe and reliable fleet operations, and to achieve the 

greatest benefit and longest life from existing fleet assets. 

Benefits of Proper Tire Inflation

Correct tire inflation, within the design limits of load and speed, reduces the risk of unexpected vehicle 

breakdown and damage, and promotes on-time freight delivery. Maintaining proper tire inflation level 

contributes to improved fuel efficiency, reduced tire wear, and longer casing life (FMCSA, 2003; TMC, 

2012; Bridgestone 2008; Goodyear 2003; Michelin 2011). Reported impacts of tire underinflation 

include approximately 5-12% degradation in tire wear for an individual tire which is 10 psi underinflated, 

and 0.5-1.0% increase in fuel consumption (degradation in fuel economy) for a vehicle running with all 

tires underinflated by 10 psi. Greater fleet productivity and protection of fleet assets can be obtained 

through effective tire inflation pressure management. Historical payback estimates for the 

implementation of tire pressure systems have ranged from less than 1 year up to about 3 years, with 

annual savings projected at $750 to over $1000 per vehicle per year.

Extent of Tire Underinflation in Commercial Vehicles

In 2003, the Federal Motor Carrier Safety Administration reported the results of a widespread data 

collection effort to document actual tire pressures on trucks during their normal operations (FMCSA, 

2003). The study collected data from more than 3200 tractors and straight trucks, and from 1300 

trailers across For-Hire TL and LTL operators, Private Carriers, and Owner-Operators. Some of the 

results reported in the study, and often cited across the industry, are listed below:

 About 1 out of 5 tractors/trucks is operating with 1 or more tires underinflated by at least 20 

psi.

 In addition, about 1 in 5 trailers is operating with 1 or more tires underinflated by at least 20 

psi.

 Nearly 3.5% of all tractors/trucks operate with 4 or more tires underinflated by at least 20 

psi.

 In addition, 3% of all trailers operate with 4 or more tires underinflated by at least 20 psi.

 Approximately 3% of all trailers, and more than 3% of all tractors/trucks, are operating with 

at least 1 tire underinflated by 50 psi or more.

 Only 46% of all tractor tires and 38% of all trailer tires inspected were within +/- 5 psi of the 

target pressure.
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To put this in perspective, the Technology & Maintenance Council of the ATA states that any tire found 

to be inflated to less than 80% of the fleet target pressure should be considered flat and immediately 

pulled from service for inspection (TMC 2012). For example, this would correspond to a condition of 80 

psi in a tire operating in a fleet that has set a target pressure of 100 psi. The above results of the FMCSA 

2003 study indicate that, while not typical, it was not unusual for an average vehicle to be operating 

with a tire in a potentially unsafe condition. However, at the time the FMCSA study was completed, 

neither the use of wide-base single tires in place of duals nor the use of any tire pressure monitoring or 

maintenance systems mounted on the vehicle were common occurrences. It would be beneficial to 

repeat a data collection effort of this type today, with the expectation that greater awareness of the 

importance of proper tire pressure, increased regulatory requirements for vehicle maintenance, and the 

wider use of tire pressure monitoring and maintenance equipment has resulted in much better 

management of tire inflation levels across the industry.

Basics of Proper Tire Inflation 

Load-Inflation tables provided by all tire manufacturers inform users on the proper inflation of their 

tires. For each tire model, the tables designate both the maximum load that the tire is capable of 

supporting and the maximum inflation pressure, which is the amount of pressure needed in order for 

the tire to carry the maximum load. The tables also recommend the required minimum inflation 

pressure for loads that are less than the maximum. Generally, the required minimum inflation level is 

set to ensure that the tire will not be operated under low-pressure conditions that could compromise 

the life of the casing. A fleet that is running tire loads that are less than the maximum indicated in the 

load-inflation tables therefore has some level of choice of operating pressure. The tire must be inflated 

to at least the required minimum inflation pressure for a given load, but can feasibly be inflated to any 

level up to the maximum inflation pressure. The target pressure selected by the fleet depends on the 

point where the best performance is observed – not just for wear, but also for braking, handling, ride 

comfort, stability, and fuel consumption.

Fleets that have been in business for some period of time will usually come to identify a level of tire 

inflation which offers optimum performance for tire wear, fuel consumption, and low maintenance, and 

which gives satisfactory vehicle performance for drivers. This may represent a single inflation pressure 

across steer, drive, and trailer tires, or may be a separate inflation pressure for each tire application. 

These levels will then be established as target inflation pressures for the fleet, often referred to as cold 

inflation pressures (CIP), meaning the pressure(s) the tires should be inflated to before the vehicle starts 

driving, normally in the morning when air temperatures are cool (ideally 65oF – 70oF). This optimum tire 

pressure depends on many variables, including equipment, routes, loads, and average environmental 

conditions for the fleet. For these reasons, the “best” tire pressure can be different from fleet to fleet.

Even once a fleet has established its target tire inflation levels, and implemented a disciplined manual 

pressure check procedure as recommended by the tire supplier, it must overcome additional 

complications in ensuring optimal inflation levels. Tire inflation pressures begin to evolve the minute a

vehicle starts rolling. For example, if the surrounding air gets warmer, inflation pressure increases. If 

the air gets cooler, inflation pressure decreases. The tire itself warms up as it starts rolling, increasing 

the pressure, while if the vehicle stops for breaks or overnight parking, the pressure usually decreases 

due to tire cooling. If the load increases the tire pressure can also increase (due to more flexing and 

heating of the tire). 
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Fleets live with this tire pressure variation every day, and establish target pressures that, on average, 

give them the best performance for their tires and vehicles. To maintain safety and durability, a fleet 

would never want to use a cold inflation pressure which is lower than the required minimum tire

inflation pressure as defined by the manufacturer. However, a fleet may want to explore how tire 

pressures fluctuate during a normal day, and whether operations can be improved by modifying existing 

strategies to maintain inflation pressure.

Along with any existing strategies a fleet may have in place, the market today offers a wide range of tire 

pressure systems which work to overcome one or more of the primary causes of tire underinflation

(FMCSA, 2007; NHTSA, 2010; Park, 2013): 

 Natural air loss due to diffusion through the tire casing, estimated at up to 2 psi per month 

(at normal tire operating pressures of around 100 psi).

 Air seepage due to a malfunctioning valve, leaking valve seals, or improper bead seating, up 

to approximately 2 psi per week to 2 psi per day.

 Slow to moderate leaks primarily due to small punctures (but may also be caused by valve or 

bead seat irregularities), up to the range of about 5 psi per hour.

 Rapid air loss, at rates of approximately 1-5 psi per minute or higher.

Sudden, catastrophic air loss is not included as a condition that can be addressed by tire pressure 

systems and is outside the scope of this study.

Different systems are designed to report and/or correct for one or more of the conditions above. 

Physical testing is outside the scope of this study, and the NACFE team has had to rely on previously 

reported test results of tire pressure system accuracy and reliability. Short term track testing of dual tire 

equalizers, TPMS, and ATIS products has shown that all of the evaluated products perform correctly in 

response to underinflated tires (FMCSA, 2007; NHTSA 2010). However, a one-year long field evaluation 

of several TPMS products in a city transit bus fleet (FMCSA, 2009) demonstrated the importance of 

training and preparation of fleet personnel for proper installation, use, and interpretation of TPMS 

components in order to achieve a successful implementation of new equipment. 

In this context, three key themes of this report are:

 The precondition for fleets to match their needs with the specific capabilities of the various

tire pressure systems when making purchase decisions.

 The importance of user readiness, in terms of personnel training and preparation of internal 

operating procedures around new tire pressure systems, to ensure successful deployment in 

the fleet.

 The need for the functionality of tire pressure systems (alerts, warnings, data reporting) to 

integrate relatively seamlessly into normal, day-to-day fleet operations without requiring 

significant system oversight or maintenance by the fleet.

A few examples illustrate the importance of these three points. For instance, an automatic tire inflation 

system will work to re-inflate a tire that has a lower pressure than the pre-set target of the inflation 

system, without adjustment for the tire temperature. That system will turn off once the combination of 
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re-inflation and tire warming brings the pressure to the target level. Track testing of re-inflation 

response times of ATIS have shown that a tire can be returned to its proper pressure within 1-10 

minutes of the start of system operation, even for initial conditions of 20-30 psi underinflation (FMCSA, 

2007; NHTSA 2010). Since the re-inflation cycle occurs rapidly, a tire will continue to increase in 

temperature and inflation pressure while driving, and may eventually exceed the target pressure. Only 

some ATIS will allow air to be released once a tire exceeds its target inflation by a certain level. 

Moreover, depending on set points of the systems, a tire may drop below the target pressure level as it 

goes through cooling when the vehicle is parked. A fleet must determine the best target pressure to 

select in light of these fluctuations. In addition, the fleet should consider the risk it is willing to accept in 

the event that an ATIS is able to mask the condition of a slowly leaking tire.

As another example, tire pressure can increase by 10-15% due to the effects of warm-up (TMC, 2012), 

which will be detected with TPMS. But most TPMS options do not include temperature compensation 

for increased pressure due to tire heating, making it possible for the system to issue a low pressure alert 

at the start of driving only to switch off the alert once the warm tire pressure exceeds the warning 

threshold. In contrast, TPMS with temperature compensation would indicate that the tire is 

underinflated even as the pressure in the tire rises in this case. From the user point of view, a fleet 

should determine in advance if this tire inflation situation is considered a false positive (e.g., the system 

gave a warning when pressure was in fact acceptable), or if it should be treated as an underinflation 

condition to be corrected immediately.

For either of the above example cases, as well as for other tire pressure technologies, the user must 

establish the operating guidelines for operators and maintenance personnel, especially in response to 

pressure alerts, in order to make effective use of tire pressure systems.

1.3 Regulatory Perspectives for Tire Pressure Systems in Commercial Vehicle Applications

Legislation Related to Use of Tire Pressure Systems on Heavy Vehicles

As of the writing of this report there were no regulatory requirements regarding the use of any tire 

pressure system on commercial vehicles with GVRW greater than 10,000 pounds. However, there have 

been four key pieces of legislation enacted over the past 15 years that may influence the future 

approach of regulators to the topic of tire pressure systems, particularly TPMS, in commercial vehicle 

applications. The mandates of these bills and the primary impacts for commercial vehicle pressure 

systems are summarized in the following table.
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Aug-13 NACFE Page 16

Exhibit 1.2 Summary of Federal Legislation Related to Tire Pressure Systems in Commercial Vehicles

Legislation Date Enacted Impacts for Commercial Vehicle Applications

TEA-21

Transportation Equity 

Act for the 21st

Century

P.L .105-178

June 9, 1998

Directed the U.S. Department of Transportation to conduct 

research on the use of sensors on trucks and tractor-trailers to 

monitor and check tire pressures. The initial FMCSA study of 

tire underinflation in the transportation industry was funded 

as a part of this legislation. The study was published in 

November 2003. (TEA-21, 1998)

TREAD Act

Transportation 

Recall, Enhancement, 

Accountability, and 

Documentation

P.L. 106-414

Nov 1, 2000

Directed the U.S. Department of Transportation to prepare 

rulemaking defining the implementation of tire pressure 

warning systems on vehicles with GVWR of 10,000 pounds or 

less, excluding motorcycles and vehicles with dual wheel 

configurations on an axle. Following the passage of the TREAD 

Act, Federal Motor Vehicle Safety Standard FMVSS 138, Tire 

Pressure Monitoring Systems mandated TPMS for light duty 

vehicles. Although the legislation did not require heavy trucks 

to install tire pressure warning systems, regulations for the 

passenger car domain may influence future requirements for 

heavy trucks and trailers. (TREAD Act, 2000)

SAFETEA-LU

Safe, Accountable, 

Flexible, and Efficient 

Transportation Equity 

Act: A Legacy for 

Users

P.L. 109-59

Aug 10, 2005

Contained provisions that modified a broad range of 

transportation research and regulatory programs administered 

by FMCSA, including ultimately the CSA program. Based on 

roadside inspections, tire inflation condition is scored under 

the Vehicle Maintenance section of the CSA BASIC system, 

with flat tires receiving a severity weighting of 8, and 

underinflated tires receiving a severity weighting of 3. This 

information is entered into CSA’s SMS scoring system, and 

used to identify any specific safety concerns for a driver or 

carrier. Use of tire pressure systems on heavy vehicles was 

not addressed in the legislation. (SAFETEA-LU, 2005)

MAP-21

Moving Ahead for 

Progress in the 21st

Century

P.L. 112-141

July 6, 2012

MAP-21 contains no discussion concerning the use of tire 

pressure systems for heavy trucks. However, the bill does 

direct the U.S. Department of Transportation to consider 

rulemaking during the following two years to address the need 

for tire pressure monitoring systems on motor coaches. In 

support of continuing work on heavy duty vehicle safety, the 

National Transportation Safety Board issued recommendation 

H-09-22 to NHTSA, advocating that all new motor vehicles over 

10,000 pounds be equipped with direct TPMS. (MAP-21, 2012)
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EPA SmartWay program

The EPA SmartWay Transport program is a partnership between government and transportation 

industry members to voluntarily seek solutions to reduce emissions and improve fuel efficiency of 

freight transport. As one part of the program the EPA verifies the fuel savings and environmental 

performance of a range of equipment and practices that are offered to commercial fleets, with the goal 

of assisting fleets in making informed purchase decisions about new technologies, both in terms of the 

effectiveness of the technology as well as the payback. By providing this information the program aims 

to facilitate the voluntary adoption of new solutions to reduce fuel consumption and lower 

environmental impacts. The SmartWay Transport program has specifically recognized the importance of 

proper tire inflation as a means to reduce air pollution and at the same time yield monetary benefits to 

the fleets.

1.4 Study Objectives 

The overall objectives of this study include:

 A synthesis of commercially available tire pressure monitoring and maintenance systems 

and their features.

 An exploration of the potential benefits and challenges for fleets related to system 

implementation.

 Examples of fleet experiences with systems that have been tested or are in use.

 Recommendations/guidelines for selecting and incorporating tire pressure systems into 

fleet operations.

Data is compiled from technical reports published by academia and government agencies, product 

information on websites and in industry publications, and direct interviews with stakeholders 

representing tire pressure system suppliers, original equipment tractor and trailer manufacturers, 

and fleet maintenance and operations managers. Testing of tire pressure systems is not included in 

the scope of the project. This report is intended to collect and share information in order to support 

fleet technology choices, as well as to discuss current trends and equipment needs that can serve as 

inputs for designers of future systems. 

Chapter 2.0 Study Approach

The approach taken by the project team during the period of the study is described in the following 

tasks:

 Initial literature review to identify and categorize types of systems for controlling tire inflation 

pressure in heavy-duty trucks and trailers.

 Online research on the commercially available systems in each category. These first two steps 

resulted in the initial identification of 8 categories and approximately 40+ potential suppliers of 

tire pressure systems. It became evident that the business of heavy vehicle tire pressure 
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Aug-13 NACFE Page 18

systems is a very dynamic industry, with nearly continuous introduction of new products, 

combined with continuous exit of products and/or companies from the market.

 Since a study of market-share-by-product was outside the scope of the NACFE Tire Pressure 

Systems project, fleets and OEMs were contacted to screen for market penetration of specific 

products. Because of the size or nature of these organizations, some tire pressure systems may 

be underrepresented or not present at all in their responses.

 Specific tire pressure systems suppliers and products were selected for in-depth interviews 

about product capabilities, market presence and maturity, and distinctive product features. 

Products selected for this portion of the study were chosen based on several factors: level of 

reported use by fleets and OEMs; the extent to which a particular product is characteristic of a 

category of tire pressure systems; and whether the product offers one or more unique features 

in its configuration, functionality, or technical approach. All products selected for this treatment 

were required to be commercially available by the end of the first quarter of 2013.

 Product summary sheets were developed for seven TPMS and five ATIS products and are 

included in Appendix A of this report. The appearance, or lack thereof, of an individual 

commercial product in this Appendix is not an indication of its performance, quality, 

functionality, or of any endorsement or recommendation by NACFE. NACFE does not endorse 

products or manufacturers. Individual products in each category can exhibit equivalent 

performance. An expanded list of tire pressure systems by category, including primary 

attributes and company contact information, is included in Appendix B. Ultimately, five major 

categories and over 30 products are cited in this report.

 The scope of the NACFE Tire Pressure Systems Project did not include testing for the accuracy or 

durability of any tire inflation product. Instead, previous product evaluations for TPMS and ATIS 

that were reported by government testing organizations were reviewed by the NACFE team 

(FMCSA, 2007; FMCSA 2009; NHTSA 2010), which included both short term track testing and a 

yearlong field test of TPMS in one city transit bus fleet. 

With respect to the products on the market today, the evaluations conducted by the study team

indicate that the intrinsic performance of all products conforms to the design and functionality 

specified by the manufacturers. Consequently, the NACFE has treated all systems as equally 

reliable and as providing equal benefit when properly used.

Clearly, if the reliability of a given tire pressure system depends on fleet personnel correctly 

interpreting and responding to system alarms consistently, and they do not, a fleet is not going 

to realize the full potential benefits of the system. 

 Risk charts have been constructed by NACFE for the main TPMS and ATIS product categories. 

Fleets can use these charts to review their readiness for adoption of a specific technology as 

well as to develop their risk response plans for a selected product type.
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 A Technology Decision Matrix was developed to identify the main characteristics and 

operational features of the various tire pressure system types.

 An ROI or payback calculator was developed for this report that considers the factors of road 

service call reduction, reduced tire replacement cost for normal operations, and fuel economy 

improvements.

 Finally, perspectives on new product features and capabilities were summarized from 

stakeholder interviews.

Chapter 3.0 Description of Currently Available Tire Pressure Systems for Commercial Vehicles

Based on interviews with tire pressure systems suppliers, other NACFE-conducted fleet surveys, and a 

review of online information sources including industry standards and recommended practices, the 

team organized tire pressure system technologies into the categories shown in Exhibit 3.1. The major 

categories are:

1. Tire Pressure Monitoring Systems (TPMS). These systems provide a direct measurement of 

pressure, and, in some cases, temperature. The measured pressure is compared to a preset target pressure determined by the fleet user for a given vehicle wheel position. If the 

tire is underinflated, maintenance staff and the driver are alerted by either a static visual 

display at the wheel-end, or by the transmission of sensor data to an in-cab display or to a 

computer system that can be accessed by the fleet. The TPMS category includes mats or 

plates containing an array of sensors that pick up and transmit the loading conditions of the 

tire footprint as the tire rolls over the surface of the mat. The mats can be embedded in 

pavement or placed on the floor of a garage. In addition, fleet-wide manual tire pressure 

check procedures are included in this category. Most of these systems can also signal an 

overpressure condition. With the exception of the floor sensor mats, all systems included in 

this report are direct TPMS, that is, systems wherein pressure is measured directly and is not 

derived from other vehicle or tire parameters.

2. Dual Tire Pressure Equalizers. In these systems, a single sensor unit is mounted to the 

vehicle wheel end, monitoring the pressure in both tires of a dual-tire assembly, with a hose 

connection to each tire valve stem. If pressure levels between the tires do not match, either 

due to temperature warming of one tire position versus the other, unequal loading, or slow

air seepage, the system will attempt to bring the inflation pressure of the two tires to the 

same level. No air is added or removed from the dual assembly by the equalizer unit. If air 

loss continues, the leaking tire is isolated and a static visual display indicates the progressive 

loss of pressure.

3. Automatic Tire Inflation Systems (ATIS). These systems monitor tire inflation pressure 

relative to a pre-set target and re-inflate tires whenever the detected pressure is below the 

target level. In general, these systems will alert the driver that re-inflation is taking place, 

but they do not report on the actual pressure in the tire. ATIS either rely on vehicle 

compressed-air tanks as an inflation medium source, or else draw air directly from the 
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Aug-13 NACFE Page 20

surrounding environment via a self-contained pump. Some ATIS equipment is capable of 

pressure relief for overinflated tires.

4. Central Tire Inflation Systems (CTIS). The operation of this type of system is similar to ATIS, 

with the difference that the driver can select the target pressure from an in-cab display, in 

order to raise or lower the tire inflation level depending on the operating conditions of the 

vehicle. Most systems of this type are intended for off-road or military truck applications.

5. Passive Pressure Containment Approaches. Another category of technologies capable of 

preventing tire pressure loss attempt to retain air in the tire once it has been inflated. 

These most commonly function by reducing natural air loss through the tire casing. 

However, certain products in this category can mitigate the effects of small punctures. Use 

of an inflation medium such as nitrogen that has a lower permeation rate than oxygen, and 

alternative means to providing barriers to air loss through the use of sealants, are 

represented in this category.

Exhibit 3.1 Classification of Tire Pressure System Technologies
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Aug-13 NACFE Page 21

3.1 Tire Pressure Monitoring Systems (TPMS)

In this study, a tire pressure monitoring system or TPMS will be distinguished from an ATIS (automatic 

tire inflation system) and a CTIS (central tire inflation system) by the following features:

 A TPMS monitors pressure and in some cases, temperature, for each individual tire. TPMS 

can identify underinflated tires by using a device that senses pressure and temperature and

in most cases, transmits the data and displays it to the operator.

 A TPMS monitors each tire based on a pre-set target pressure, and issues alerts based on 

the difference between the target pressure and the actual measured pressure in the tire.

Types of Tire Pressure Monitoring Systems

Current TPM systems are separated into two fundamental types, depending on the positioning of the 

sensors: 

 External valve stem mounted/External wheel mounted tire pressure monitors. External 

valve stem mounted tire pressure monitors use sensors that are mounted to the end of the 

valve stem in place of the valve stem cap. The sensors monitor the air pressure of the tire 

and, in some systems, monitor the wheel end temperature. The sensors then transmit the 

data from the tire to a transceiver/repeater and on to an in-cab display. There are some 

systems that transmit directly from the sensors to an in-cab display. External wheel 

mounted tire pressure monitors use sensors that are mounted to the wheel. The sensors 

are mounted with a bracket and then hoses are run from the sensors to the valve stem. This 

subtype is then further broken down based on how the pressure data is displayed to the 

operator, as they may use either an in-cab display or may require a visual walk-around of 

the tractor/trailer by the operator. External TPMS can be used on tractor, trailer or in 

combination.

 Internal valve stem mounted/Internal wheel mounted/Tire casing mounted tire pressure 

monitors. Internal valve stem mounted tire pressure monitors use sensors that are 

mounted internally at the base of the valve stem. The sensors monitor the air pressure and 

in some cases temperature. Internal wheel mounted tire pressure monitors use sensors 

that are mounted to the wheel with a band or strap. The sensors monitor both the air 

pressure and the temperature inside the tire envelope. Both of the above sensor types are

either read by a receiver/transceiver or transmit their data to a receiving ECU/antenna. The 

signal is then transmitted to the in-cab display. The in-cab display will alert the driver, in real 

time, to any tire pressure loss or temperature increase. Some of these systems will also 

report corrected tire pressure derived from the tire’s internal temperature at the time. Tire 

casing mounted tire pressure monitors use a sensor mounted in the summit area of the 

tire. The sensor, inside a rubber container, is glued onto the tire casing. Each sensor 

monitors tire pressure and temperature. This data is sent from the sensor to the ECU 

antenna mounted on the tractor, and then transmitted to the in-cab display. The display 

will then alert the driver to any tire pressure or temperature event. Internal TPMS can be 

used on tractor, trailer or in combination.
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3.1.1 Non-Transmitting Wheel-End Sensors

Non-transmitting wheel-end tire pressure monitors use sensors mounted to the end of the valve stem. 

This is the most basic type of TPMS because it does not transmit the tire pressure data. The sensor will 

simply provide a visual indication of the tire pressure, requiring the operator to do a “walk-around” of 

the tractor and trailer in order to see the tire pressure reading. This type can be used on tractor, trailer,

or in combination.

3.1.2 Transmitting Wheel-End Sensors

Two distinct advantages of TPMS of this type are that:

 They obtain a direct measurement of the actual pressure for each individual tire that contains a 

sensor. The pressure condition for each tire is reported to the operator or to fleet maintenance 

personnel during both normal operating conditions as well as for pressure alerts. (As will be 

discussed later, ATIS installations will generally connect all tires to a central control unit, and a 

typical ATIS will not report actual pressure for individual tires or indicate which tire is 

experiencing a low-pressure issue.)

 TPMS can link to existing vehicle communications networks to transmit tire pressure data and 

other tire condition information to Internet and cell phone systems. A fleet may choose to have 

the initial notification of a tire with low pressure sent to fleet maintenance personnel to 

determine what action should be taken, rather than to a driver. Data can be collected in central 

databases and analyzed for tire performance trends, and may also link to a fleet’s work order 

system for tire inspection and maintenance scheduling. 

3.1.2.1 External Valve Stem Mounted/External Wheel Mounted Tire Pressure Monitors

System Components

Sensors. The sensors used in this type of TPMS are wireless. Each sensor is mounted on the valve stem 

in place of the valve stem cap or on the outside of the wheel with a mounting bracket. The sensors 

transmit tire information through an RF signal to the in-cab display, a hand-held tool, or a gate reader. 

Most suppliers offer a standard sensor and an industrial sensor for large bore valve stems. The sensor 

transmission distance may vary, but most suppliers claim up to 300 feet. The sensor weight varies with 

supplier, from 2/3 oz. to .83 oz. Each sensor contains an internal battery that cannot be recharged or 

replaced. The average battery life claimed by suppliers varies from 3 to 5+ years, (FMCSA, 2007; 

Interviews with Industry Stakeholders) depending on the frequency of monitoring and transmission of 

tire information. 

Transceiver. A transceiver is used to transmit data wirelessly from the sensors to an in-cab display. Not

all systems employ transceivers. 

Intelligent Gateway/Repeater. Many TPMS include an intelligent gateway along with a repeater, which 

are used to accept a signal from the sensor and transfer it to the vehicle network. The gateway can be 

mounted inside or outside of the tractor, while the repeater is mounted outside of the trailer. The 
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Aug-13 NACFE Page 23

transmission of the signal is not done wirelessly, however, and will need power from the tractor to the 

gateway and from the tractor to the trailer for the repeater. The transmission distance capability may 

vary, but most suppliers claim a range of 100 feet to 1000 feet. Most repeaters can collect and transmit 

information for up to 16 tires. When a gateway is used with a repeater, the gateway can read up to 160 

tires. Gateways and repeaters do not have operator interface capabilities. Instead, an in-cab display is 

used for sensor monitoring by the operator. 

In-Cab Display. The in-cab display is used as the interface between the operator and the tire sensors. 

The display enables the operator to monitor tire pressure and sometimes temperature of each tire. 

Most displays continuously monitor the tire pressure and temperature data transmitted from the 

wireless sensors. This data is then shown on the display in various forms from actual tire pressure 

readings, actual tire temperature readings, audible alerts (fast leak, low pressure, and high pressure), 

and visual symbols and flashing light alerts. The maximum number of wheel positions that can be 

displayed, and the display layout, vary from system to system. The in-cab display is either mounted in 

the instrument panel or to the bottom of the over-head console. Some systems require that the display 

be mounted near the windshield to enable satellite communication. 

Gate Reader. Gate readers are optional devices offered with some systems. They automatically collect 

tire data every time the tractor and trailer come into the yard. The gate reader could be mounted at 

various points in the yard, for example at the entrance/exit gate or at the fuel island. This data is then 

transmitted to internal software that the company maintains (or in some case to a web portal), where 

maintenance personnel can see the data and determine the best course of action. These devices may 

not be the best for long-haul fleets that are away from central terminals for long periods of time.

Hand-Held Programming/Receiving Tool. Hand-held programming tools are optional devices that are 

offered with some systems. They can be used for programming each tire position and to wirelessly 

collect tire data. They are then used with internal software that the company maintains. A physical 

“walk around” of the vehicle is required for programming each sensor. This option may work best for 

small fleets. 

Tire Hoses. Tire hoses are used with some systems to connect the wheel-end mounted sensor to the 

tire valve stem. Most systems that use hoses also offer a quick fill port so the hose does not need to be 

removed from the tire valve stem in order to add air to the tire.

Overview of Functionality of External Valve Stem/External Wheel Mounted TPMS

The following schematics (Exhibit 3.2 and Exhibit 3.3) show the basic functionality of an external valve 

stem/external wheel mounted TPMS system. As described earlier, each sensor is mounted either on the 

end of the valve stem or on the wheel-end itself. Each sensor detects the tire pressure and also, with 

some systems, tire temperature, and then wirelessly transmits this data to the transceiver/repeater, 

which will then send the signal to the in-cab display or else the sensors simply transmit the signal 

directly to the in-cab display. It is important to note that on some of these systems, tire temperature 

data represent the temperature measured at the wheel end and not the internal tire temperature. 

Systems that measure and compensate for internal tire temperature will be discussed in the next 

section. The signal is then received by the in-cab-display that will allow the operator to monitor the 

pressure and temperature of each tire position. Some of these systems also offer a ‘drop and hook’ 
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feature for trailers. When a tractor changes trailers, a transceiver on the front of the trailer transmits 

the sensor IDs and wheel positions from the trailer tires directly to the in-cab display unit automatically. 

No system reprogramming is required to identify the sensors from the new trailer to the tire pressure 

system. Several systems allow this capability for multiple trailers connected to the tractor.

Exhibit 3.2 External Valve Stem/External Wheel Mounted TPMS (with Transceiver/Repeater)
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Aug-13 NACFE Page 25

Exhibit 3.3 External Valve Stem/External Wheel Mounted TPMS (direct transmission to in-cab unit)

Tire pressure monitoring systems of this type should include the following capabilities (additional 

general system requirements are described in SAE J2848-1):

 Directly detect and report the tire inflation pressure for each individual tire that has been 

equipped with a pressure sensor. 

 Warn the driver and/or other fleet personnel of any tire that is underinflated according to 

fleet established alert levels for tire pressure. The system should identify the specific tire 

with the low-pressure condition, and report the actual inflation pressure of the tire.

 Report tire pressure at any time during normal operation of the vehicle, not just during 

alerts.

 Accommodate use on tractor-only, trailer-only, or combined tractor-trailer systems, 

including multi-trailer vehicle configurations, with reporting to a single in-cab display or 

monitor.

 Allow trained and authorized fleet personnel to adjust target pressure or alert levels at the 

fleet site or in the field.

 Provide indication to driver or other fleet personnel of any system or sensor malfunction, 

with diagnostics to help identify the nature of the malfunction, and continue to operate 

properly for remaining sensors in the event of the loss or damage to an individual sensor.

 Sensors should not affect tire performance, or characteristics of the tire/wheel assembly 

such as balance or proper tire/wheel interface integrity.
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 Sensors should function under all conditions normally encountered during vehicle 

operation, such as speed, ambient temperature, and vehicle maneuvers. 

 Optionally, the system may measure and report temperature, which could be used to determine 

overheating at a wheel-end location.

 Optionally for systems connecting to the vehicle CAN, the system should respect the 

requirements for vehicle communications described in the SAE J1939/1 recommended practice.

Potential Risks Related to External Valve Stem/External Wheel Mounted TPMS

Field or lab testing of the different commercial systems was outside the scope of the NACFE study. 

Existing publicly available studies of TPMS that compare the performance of different systems indicate 

that currently available systems function largely as designed by their manufacturers (FMCSA, 2007; 

FMCSA, 2009; NHTSA, 2010). However, different types of systems may present different risks due to 

their specific components or configuration, or due to the way fleet maintenance and operations 

functions must interact with the system. For these reasons, the NACFE team compiled a list of potential 

risks associated with the use of TPMS as an aid for fleets evaluating the implementation of this

technology into their operations.

Although there is always the possibility that a given risk may occur, it is also possible that the risks listed 

below will not occur at all, or will occur only with very low frequency. In any case, fleet management 

should execute a risk analysis and develop at least a basic risk response plan before investing in an

extensive system installation. 

Risks are divided into the following categories: Operations, Equipment, Damage, Electrical, and Leakage.

Exhibit 3.4 Potential Risks Associated with Use of External Valve Stem/External Wheel Mounted TPMS

RISK IMPACT

Operations (interactions between tire pressure systems and fleet operations)

Maintenance and management 

attention

A fleet may not have sufficient resources to devote to any external 

TPMS if the system requires increased attention or oversight to 

function properly.

Driver/Operator misinterprets

warning light/system operation 

(or frequent turnover of drivers)

The warnings could be ignored, negating the benefits of the TPMS.

Technician does not understand 

system installation or operation 

(or frequent turnover of 

technicians)

Installing sensors correctly is very important, especially when 

reinstallation is required. It is important to make sure the correct 

sensor is re-installed in its original tire location. 

Component theft No recorded tire data and the expense of replacement

False alerts Inaccurate/false readings that may affect future operator response 

to the system.

Additional maintenance item Include in preventive maintenance schedule.
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Equipment

Sensor installation Certain sensor types may be hard to tighten on aluminum wheels 

due to hand hole size.

Sensor size or weight Fatigue and vibration on the valve stem causing air leaks.

Battery life shorter than 

expected by fleet

Batteries cannot be replaced; new sensor must be purchased and 

installed.

Damage 

Sensor or tire hose damage from 

flying debris Inaccurate or missing tire pressure information

Tire hose chafing against sharp 

or metal edges (for certain 

system types)

Inaccurate or missing tire pressure information

Tire hose damaged from contact 

with wheel, stretching, or slack 

allowing hose to extend past 

wheel (for certain system types)

Inaccurate or missing tire pressure information

Electrical 

Power loss to 

transceiver/repeater May cause the system to be inoperable

Loose wires, electrical shorts May cause the system to be inoperable

Leaks (most important Risk category) 

Leak in tire hoses or at valve 

stem due to interaction with tire 

hose (for certain systems) or 

sensor

Tires can deflate when vehicle is parked

(FMCSA, 2003; NHTSA, 2010; FMCSA, 2007; Doran, 2007; AirBAT RF®, 2012; Pressure ProTM, 2013; Tire

Vigil, 2013; Interviews with Industry Stakeholders)

3.1.2.2 Internal Valve Stem Mounted/Internal Wheel Mounted/Tire Casing Mounted TPMS 

System Components

Sensors. The sensors used in the various internal TPMS are also wireless. There are three sensor

mounting locations: internal to the tire/wheel assembly at the base of the valve stem; on the wheel 

using a band or strap; or on the tire casing under the tread area of the tire. The sensors monitor tire 

pressure and temperature in real time. Each sensor is read by a receiver/transceiver or transmits the 

data to a receiving ECU/antenna. The sensor weight varies with supplier, from 1 oz. to almost 2 oz. 

Each sensor contains an internal battery that cannot be recharged or replaced. The average battery life 

claimed by the suppliers varies from 5-7 years. (FMCSA, 2007; Interviews with Industry Stakeholders)
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 28

Receiver/Transceiver or ECU/Antenna. A receiver/transceiver or ECU/antenna is used to transmit both 

tire pressure and temperature data wirelessly from the sensors to an in-cab display. In some systems 

this is also used as the wireless device for a drop-and-hook feature for trailers. 

In-Cab Display. The in-cab display is used as the interface between the operator and the tire sensors. 

The display enables the operator to monitor the tire pressure and temperature of each tire. Most in-cab 

displays continuously monitor the tire pressure and temperature data as transmitted from the wireless 

sensors. This data can be shown on the display in various forms from actual tire pressure readings, 

actual tire temperature readings, audible alerts (fast leak, low pressure, and high pressure), and visual 

symbols and flashing light alerts. The maximum number of wheel positions that can be monitored by a 

single display varies from system to system. The in-cab display is mounted in the instrument panel.

Trailer Lamp. The trailer lamp is mounted to the forward face of the trailer and is visible to the driver 

through the driver’s side mirror. The lamp will illuminate when there is a loss of tire pressure. 

Hand-Held Programming/Receiving Tool. Hand-held programming tools are optional devices that are 

offered with some systems. They can be used for programming each tire position and to wirelessly 

collect tire data. A physical ‘walk around’ of the vehicle is required for programming each sensor. This 

option may work best for small fleets. 

Overview of Functionality of Internal Valve Stem/Internal Wheel Mounted/Tire Casing Mounted TPMS

The following schematic (Exhibit 3.5) shows the basic functionality of an internal wheel mounted/tire 

casing mounted tire pressure monitor. As described earlier, each sensor is mounted to wheel or to the 

inside of the tire. Each sensor monitors the tire pressure and tire temperature, and then either 

wirelessly transmits this data or a transceiver/receiver or ECU/antenna, which will then send the signal 

to the in-cab display. It is important to note that these systems monitor the actual tire temperature, 

and in some systems, compensate for tire temperature in the pressure reading. The signal is then 

received by the in-cab-display that will allow the operator to monitor the pressure and temperature of 

each tire position. There are some systems that offer the option of a hand-held tool that allows the 

operator or maintenance personnel to program/reprogram the tire sensors and collect tire data. A 

‘walk-around’ by the operator of the tractor and trailer is necessary for sensor programming or data 

collection. 
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Exhibit 3.5 Internal Valve Stem/Internal Wheel Mounted/Internal Tire Mounted TPMS

Exhibit 3.6 Internal Valve Stem/Internal Wheel Mounted/Internal Tire Mounted TPMS:

Tractor-Trailer Configuration
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Aug-13 NACFE Page 30

Tire pressure monitoring systems of this type should exhibit the same capabilities as the external type 

with the addition of the item below. 

 The tire pressure system should be able to compensate for the effect of temperature, and to 

distinguish between an observed change in tire inflation pressure due to tire heating or 

cooling or due to an observed pressure change caused by actual loss of inflation gas.

The internal tire casing mounted tire pressure monitors should also exhibit the following key features in 

addition to those mentioned earlier: (FMCSA, 2003)

 Integration of a sensor/transmitter in a single electronic device.

 Lightweight and small packaging.

 Ability to withstand high temperature, shock, and vibration of normal tire operation and 

deflection cycles.

 Ability to sense pressure and tire temperature, and to monitor these parameters 

continuously.

 Ability to “permanently” record various tire-related data such as unique tire ID numbers, 

and history of incidences of low and high pressure or temperature. 

Potential Risks Related to Internal Valve Stem/Internal Wheel Mounted/Tire Casing Mounted TPMS

As indicated in the earlier discussion of external valve stem/external wheel mounted TPMS, different 

types of systems may present different risks due to their specific components or configuration. In 

comparison with the previous risk chart for external sensor TPMS, the NACFE team has separated out 

potential risks associated with the use of internal sensor TPMS as an aid for fleets evaluating the 

implementation of the technology into their operations.

Again, because a risk may or may not occur, fleets should perform a risk analysis and develop a risk 

response plan before investing in a tire pressure system.

Risks are divided into the following categories: Operations, Equipment, Damage, Electrical, and Leakage. 
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 31

Exhibit 3.7 Potential Risks Associated with Use of Internal Valve Stem/Internal Wheel 

Mounted/Internal Tire Casing Mounted TPMS

RISK IMPACT

Operations (Interactions between tire pressure systems and fleet operations)

Maintenance and management 

attention

A fleet may not have sufficient resources to devote to any internal 

TPMS if the system requires increased attention or oversight to 

function properly.

Driver/Operator misinterprets warning 

light/system operation (or frequent 

turnover of drivers)

The warnings could be ignored, negating the benefits of the TPMS.

Technician does not understand system 

installation or operation (or frequent 

turnover of technicians)

Installing sensors correctly is very important, especially when 

reinstallation is required. It is important to make sure the correct 

sensor is installed in its original tire location. 

Sensor Improper installation of the sensor may push the tire off center and 

may cause the sensor band or strap to be sheared off.

Equipment

Battery life shorter than expected by 

fleet

Batteries cannot be replaced; new sensor must be purchased and 

installed.

Damage 

Sensor (general) May be damaged during tire mounting/demounting

Sensor (general)

Performance of internal sensors may be degraded due to 

contaminants inside the tire envelope, such as oil, water, sealants, 

or other debris.

Sensor (tire casing mounted) Sensitivity or damage due to summit location of sensor, resulting 

from normal rolling cycle of tire or road shock to tread area.

Electrical 

Power loss to transceiver/repeater May cause the system to be inoperable

Loose wires, electrical shorts May cause the system to be inoperable

(FMCSA, 2003; NHTSA, 2010; FMCSA, 2007; SmarTireTM 2010; Valor 2013; Interviews with Industry 

Stakeholders)

3.1.3 Pressure Sensing Mats

Pressure sensing “mats” or “plates” have been developed by a small number of suppliers as a means to 

quickly measure and report the tire inflation condition automatically as a vehicle enters a garage or 

service center. A matrix of sensors is arranged into a metal plate structure that can be installed into an 

indoor floor or driveway surface. In a typical configuration, each sensor records an incremental load on 

the sensor area as a tire is driven across the plate at low speed. By reconstructing the history of sensor 

loading as the tire passes, the system is able to determine the shape and contact area of the tire 
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 32

footprint and the total load being carried by the tire. This information is used to calculate the tire 

inflation pressure.

The sensor mat is connected to a portable floor display unit that reports pressure for each individual tire 

on the vehicle, including tires mounted in dual configuration. Not all system descriptions state whether

they are compatible with wide base single tires. The display unit includes warning lights that will turn 

green if all tires are properly inflated or red if a tire needs service. The unit may also indicate if there is 

an unacceptable difference between two tires of a dual assembly, even if each individual tire would not 

trigger a low-pressure warning. Some systems are configured to record the vehicle license plate or ID 

number as it passes over the sensor plate, and transmit the vehicle and tire information to a fleet 

management database.

This type of system does not require any equipment installation or modification on the vehicle itself. All 

system components are placed in a single centralized location per depot or service center. Pressure 

measurements can be obtained rapidly and automatically for all tires on a vehicle without any manual

intervention. 

Although the effects of load on the tire contact area is automatically taken into account, it is unclear if 

currently available pressure sensing mats can compensate for pressure variations from tire heating due 

to rolling or environmental conditions. Users would need to carefully determine the pressure tolerance 

limits for their specific operations in order to avoid false pressure warnings from the system while also 

setting sufficiently tight control ranges to ensure that proper tire inflation is maintained. Sensor 

measurements may be affected by normal contaminants such as dust, oil, dirt, and moisture that are 

frequently present at fleet sites. Certain pressure mats or plates may be better suited to a controlled 

test environment rather than a commercial fleet setting.

Technology of this type will be most effective in an application where vehicles return to a terminal or 

central location daily, or at least on a frequent basis. 

3.1.4 Manual Tire Pressure Check Procedures in Fleets

An air-pressure maintenance program to manually check tire pressures is recommended for all fleets –

those who do not use tire systems such as TPMS or ATIS, as well as for those fleets who have adopted a 

commercial tire pressure system. 

Effective manual tire pressure programs normally plan for an inflation check of each tire at least once 

per week. Fleet fueling stations and the maintenance garage are the most common locations for tire 

pressures to be checked at the fleet terminal. The need for fleets to re-fuel vehicles every day or every 

few days makes the fuel island a good location to perform tire checks as well as other vehicle 

inspections, and tire pressure verification can be included in a checklist of duties to be completed while 

the vehicle is at this station. Drivers or other fleet personnel are usually assigned the responsibility of 

checking tire inflation. In practice, there is approximately a 50/50 split among fleets in the industry that

require drivers to perform tire pressure checks versus those who assign this task to other, most often 

maintenance, employees. Generally, a manual, or hand-held pressure gauge is used to measure tire 

inflation pressures.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 33

For fleets whose vehicles may be away from terminals or service centers for extended periods, drivers 

generally carry the responsibility of maintaining proper tire inflation. This inspection can be 

accomplished by the driver while at truck stop fuel islands, or a fleet may contract with truck stops or 

other service providers to perform routine pressure checks while the vehicle is on the road.

As a spot check, tire manufacturers may offer tire inspection or audit services to fleets on a quarterly or 

semi-annual basis. During these inspections, trained tire personnel will check inflation pressures,

examine tires for damage conditions, summarize and report results, and recommend actions for fleets 

to improve their tire management practices. While these audit programs cannot ensure day-to-day 

conformance to fleet tire pressure targets, they can provide the fleet with independent feedback about 

the effectiveness of their operations to control and maintain tire pressure. 

Key elements of a successful manual tire pressure maintenance program include:

 Clear designation of who is responsible for checking tire pressure.

 Specifying fleet target pressures for all wheel positions.

 Documenting the required frequency and procedures for routine tire pressure checks, and 

communicating that information to fleet personnel.

 Providing suitable gauges to drivers or maintenance technicians.

 Creating and following a calibration program for tire pressure gauges.

 Making sure the program is followed consistently.

3.2 Dual Tire Pressure Equalizer Systems

Even if all tires are properly inflated initially, a difference in the pressure between the inner and outer 

tires of a dual tire assembly can develop during vehicle operations. This condition may occur if the tires 

are subjected to unequal heating or cooling due to environmental effects, such as direct sunlight, 

unequal loading between the inner and outer tire, which may occur due to axle bending under load, or 

slower air seepage in one tire versus the other. Because the two tires are bolted together, they are 

forced to rotate at the same rate independent of their relative inflation pressures. This will often result 

in development of faster wear and/or irregular wear of the tire with a lower inflation pressure. Most tire 

manufacturers recommend that tires in a dual assembly be within 5 psi of each other.

Dual tire pressure equalizer systems are designed to maintain the same inflation pressure between the 

two tires in a dual assembly. Typically, a central sensor unit is attached to the outer wheel, with tire 

hoses running from the unit to the valve stems of both tires. The unit allows air to flow back and forth 

between the two tires, but does not add or remove air during normal operation. For example, if the 

temperature of the outer tire rises faster than that of the inner tire, resulting in a higher pressure at the 

outer tire, the equalizer system will slowly transfer air to the inner tire, until both tires are operating at 

the same pressure. Conversely, if one tire of the dual assembly is leaking, the system will transfer air 

from the non-leaking tire in an attempt to balance the pressure between the tires.

For either slow, continuous leaks, or for instantaneous air loss in one tire, the system will attempt to 

maintain the same pressure in both tires until the combined pressure drops by a pre-set threshold level -

frequently about a 10 psi reduction across the system - at which point the check valve of the control unit 

will close, isolating both tires. 
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 34

Typically, the unit operates in the target range of 60-130 psi, allowing the operator to select a model 

with the desired target pressure. Different models can be selected per axle position. Most systems 

include a central fill valve that permits the user to replenish air to both tires without having to remove 

the hoses. 

Dual tire equalizer systems usually include some type of visual display mounted to the hub unit that 

provides an indication of the air pressure condition for the tires. This is generally a qualitative go/no-go 

gauge that will show if tires are within the normal pressure range, or are under- or overinflated. 

However, the operator cannot be certain of the severity of underinflation if the display signals a low 

pressure condition.

Possible risks associated with the use of dual tire pressure equalizers are categorized into equipment 

and damage. The valve that operates in these systems may wear over time and it is important to 

monitor and potentially replace it. The gauge and hoses may become damaged due to road debris and 

normal wear. If these risks occur, the system may not function correctly and/or inaccurate readings and 

diminished airflow can result.

3.3 Automatic Tire Inflation Systems (ATIS)

For the purpose of this study, an automatic tire inflation system, or ATIS, will be distinguished from 

TPMS (tire pressure monitoring system) and CTIS (central tire inflation system), by the following 

features:

 The ATIS will operate automatically to restore the tire inflation pressure to its target or 

specified level, that is, without requiring any manual intervention to initiate re-inflation.

 The system will function to maintain target pressure across a normal or typical range of 

ambient operating conditions.

 The system is pre-set to one single target pressure, or to a single target pressure per control 

unit, this target value being non-adjustable by the vehicle operator from inside the cab 

during vehicle use.

 Actual tire pressure is typically not reported for the tire/wheel assemblies connected to the 

system.

The distinction between ATIS and CTIS is considered to be the ability of the CTIS to respond to ondemand changes in target pressure which can be achieved with a user interface inside the cab. In 

contrast, ATIS are generally designed for single target pressure. Further elaboration of the functionality 

and evaluation of ATIS can be found in SAE Recommended Practice J2848-2.

Types of Automatic Tire Inflation Systems (ATIS)

Current ATIS are largely separated into two fundamental types, based on air supply, which determines 

whether the systems are considered to be centralized or distributed.

 The most common type of ATIS is a centralized system in which components are connected to 

the vehicle compressed air supply, most often the trailer air tank that also supports the braking 

system of the vehicle. Typically, a series of air lines will run from the trailer air tank to the wheel 
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 35

end, with hoses positioned at the hubcap to route air to the valve stem of each tire. The system 

is compatible with dual or wide-base single tire configurations. At present, deployment of this 

category of system is usually limited to trailer applications, taking advantage of the hollow axle 

to deliver air. It is clear that the drive shaft contained within the housing of the tractor axles

prevents this strategy from being used on drive axles.

 A second type of ATIS uses self-contained pumps either within individual tires or with one 

system per wheel end. The system is considered to be “distributed” because there is not a 

central control for all tires. This type of ATIS relies on rotational motion and deformation of the 

rolling tire to create pressure gradients that in turn cause the system to deliver atmospheric air 

(air surrounding the vehicle) directly into the tire. Although the study team was able to identify 

several patented systems, and instances of these types of systems in development, the 

availability of commercial or near-commercial products in this category is extremely limited. 

Nonetheless, because the technical methodology used by these systems represents a 

fundamentally different approach to tire inflation a characteristic ATIS of this type was selected 

for inclusion in this report. Since the air supply is not dependent on a vehicle air tank, use of this 

ATIS technology does not depend on availability of hollow axles, and the systems can support 

both drive and trailer axles. Either dual or wide-base single tire arrangements can be 

accommodated.

Four Types of Pressure Losses

All ATIS in today’s market work to overcome one or more of the following causes of tire underinflation. 

To date, the boundaries between each type of pressure loss are not strictly defined. Characteristic air 

loss rates are indicated to provide an idea of severity of each type of underinflation mechanism.

Catastrophic or sudden and complete air loss is not included, as it is not considered to be an appropriate 

condition to be addressed by ATIS technology.

 Natural tire pressure loss due to air diffusion through the tire body. Air losses occur very 

slowly, and are estimated to be up to 2 psi per month for commercial vehicle tires. The actual 

leak rate depends on tire construction and the existing inflation pressure.

 Air seepage between the tire and the wheel in the bead seat zone, and at improperly tightened 

or leaking valve stems, cores, or seals (any tire interface, or any internal air chamber interface). 

In some cases, low temperatures may cause temporary leakage at these interfaces, which could 

subsequently become airtight as the outdoor temperature or tire temperature increases. 

Observed leak rates may be in the range of 2 psi per week to 2 psi per day.

 Slow to moderate leaks from valve or bead seat irregularities or small punctures, up to an air 

loss rate of about 5 psi per hour.

 Rapid air loss, due to more significant punctures, with loss rates of approximately 1-5 psi per 

minute or higher, excluding catastrophic air loss occurrences.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 36

3.3.1 ATIS Type 1 – Vehicle Tank Air Source

System Components

The following section describes the components that are commonly found in this type of system. For 

the purpose of discussion, the air source will be assumed to be the trailer air tank, as is the case for most 

currently available ATIS Type 1.

Control Unit. The control unit contains the components that will manage airflow from the trailer air 

tank to the tires. This is primarily accomplished through a pressure regulator inside the control box that

is pre-set to the target pressure requested by the fleet user for their specific equipment and operating 

parameters. Most suppliers of ATIS Type 1 provide a means for the fleet user to adjust the target 

pressure setting via a knob on the regulator, or other method. However, field adjustment of the target 

pressure is discouraged. 

The regulator is designed for one-way flow of air to the tires. All tires connected to a given regulator will 

be controlled to the same target pressure. If a different target pressure by axle is desired, an additional 

regulator must be included in the control unit and set to the second target pressure. This situation 

could occur in the case of a trailer lift axle fitted with a different tire size than on the stationary axle 

positions.

A flow switch, or alternatively a pressure sensor, in the control unit is used to signal when the inflation 

system is operating to rectify an underinflation condition. The detection system is wired to an indicator 

lamp on the front of the trailer, which warns the driver that the system is working to inflate one or more 

tires. This is usually the only electrical component of the inflation system. Air flow higher than a certain 

threshold, or pressure below a certain threshold, will cause the warning lamp to be turned on. If a 

vehicle is starting its operation from cold tire conditions – for example after being parked all night – the 

trailer warning light may be on for 10 minutes while tires are warming up and the system is inflating to 

target pressure. Continuous illumination of the warning lamp indicates a tire inflation problem, or more 

rarely a system malfunction, that should be investigated.

The control unit may include components that regulate a pressure relief function for cases where tire 

pressure is higher than a certain level, say 10 psi above the target pressure. If the tire pressure 

increases to the overpressure set point, air is routed back through the control unit to an exhaust port. 

Note that this is a venting function for the tires only, and is not the same as the axle vent used to release 

pressure build-up inside the hollow trailer axle in the case of overheating or emergency operation of 

wheel-end components.

Shut-off Valve or Air Tank Protection Valve. This component isolates the air tank from the tire inflation 

system in the event of low tank pressure in order to protect the braking capacity of the vehicle. It is 

located between the air supply tank and the control unit.

Hubcap Assembly. The purpose of the hubcap assembly in an ATIS Type 1 is to link the stationary air 

supply system with the rotating wheel assembly. The rotary union is perhaps the key component of the 

assembly, being the part of the system most susceptible to wear. Reliability of the rotary union is critical 
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 37

to the good functioning of the system, and most ATIS suppliers have spent considerable research and 

development effort to achieve optimal performance and durability of this component. 

Air lines. Air lines run from the control unit to a delivery system supplying air to the tires. This is 

accomplished in one of two ways: 1) air hoses run to connections placed in drilled holes in the axle, such 

that the entire hollow trailer axle is pressurized; or 2) air hoses continue through the non-pressurized 

axle directly to the wheel end. This latter configuration allows airflow back to the control unit from each 

tire in certain ATIS Type 1 products, permitting the tire pressure relief or venting functionality.

Tire hoses. Hoses are connected from the hubcap assembly to the tire valve stems for final delivery of 

air to the tire envelope. Check valves are integrated into the hoses or the hubcap to isolate a 

continuously leaking tire from the rest of the tire inflation system.

Exhibit 3.8 is a schematic of the primary airflow routes through the main components of an ATIS Type 1. 

In this example, air lines are shown as running through the hollow trailer axles. In an alternative system 

configuration (not shown), air is pressurized within the axle tube, eliminating the secondary tee-fitting 

connections and air lines within each axle.

Exhibit 3.8 Configuration of ATIS Type 1 – Vehicle Tank Air Source
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Aug-13 NACFE Page 38

Overview of Functionality of ATIS Type 1

Tire inflation systems of this type should be capable of: (additional general system requirements are 

described in SAE J2848-2)

 Compensating for the natural tire pressure loss due to diffusion through the tire body. Since 

this phenomenon is occurring on all tires at the same time, the system must be able to 

supply air to all tires connected to it at this rate.

 Compensating for other conditions of relatively low leak rates such as air losses between the 

tire and the wheel in the bead seat zone, or at improperly tightened or leaking valves stems 

or cores. As above, the system must be able to supply air to all tires connected to it 

simultaneously at this rate.

 Compensating for moderate leaks from small punctures.

 Compensating for certain rapid air loss incidents. (The system cannot compensate for 

catastrophic air loss.)

 Maintaining the tire pressure difference between two tires in a dual assembly to 5 psi or 

less.

 Providing an indication to the driver when the system is functioning to replenish tire air 

pressure.

 Providing an indication of system malfunctions to the driver or maintenance personnel.

 Providing an indication to the driver when system is unable to compensate pressure loss of 

a tire.

 Isolating the system from a fast leaking tire or during a tire change out.

 Isolating the air tank from the tire inflation system to preserve functionality of braking or 

other systems supported by vehicle air supply.

 Providing clean, moisture-free air supply.

 Preventing contamination of system by oil, dust, moisture, chemicals, or other 

contaminants.

 Providing a system of axle venting, in case of malfunction or overheating of other wheel-end 

components.

 Optionally: providing ATIS pressure relief function to prevent over-pressuring of tires.

Potential Risks Related to ATIS Type 1

Field or lab testing of the different commercial systems was outside the scope of the NACFE study. 

Existing publicly available evaluations of ATIS that examine the short-term test-track performance of 

various products indicate that functioning of currently available systems is largely as designed by 

manufacturers (FMCSA, 2007). However, different types of systems may present different risks due to 

their specific components or configuration, or due to the way fleet maintenance and operations 

functions must interact with the systems. Macro results of a single field operational test of ATIS Type 1

have been presented (FMCSA, 2011), but the complete, finalized report has not been published to date. 

In the absence of medium- to long-term system durability data, the NACFE team compiled a list of 

potential risks associated with the use of ATIS Type 1 as an aid for fleets evaluating the implementation 

of the technology into their operations.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 39

Although there is always the possibility that a given risk may occur, it is also possible that the risks listed 

below will not occur at all, or occur only with very low frequency. In any case, fleet management should 

execute a risk analysis and develop at least a basic risk response plan before investing in extensive 

system installation. 

Risks are divided into the following categories: Operations, Equipment, Damage, Contamination, 

Leakage, and Electrical. 

Exhibit 3.9 Potential Risks Associated with Use of ATIS Type 1 - Vehicle Tank Air Source

RISK IMPACT

Operations (interactions between tire pressure systems and fleet operations)

Tractor tires cannot be managed 

by automatic tire inflation 

system

75% of tire breakdowns are on the trailer; 25% are on the tractor 

(FMCSA, 2003), even though occurrences of low pressure as 

measured in the field are approximately the same between tractor 

and trailer applications. The majority of ATIS products cannot 

prevent drive/steer tire breakdowns.

ATIS installed on trailers due to 

be traded within 2-3 years

May not realize payback of system before it is traded.

Trailer air tank pressure is lower 

than target tire inflation 

pressure

Tire cannot be inflated to target. 

Target inflation pressure for tire 

is too close to cutoff pressure of 

Pressure Protection Valve (PPV)

PPV will isolate tire inflation system from trailer air tank at about 70-

80 psi for most systems in order to protect braking function of 

vehicle, cutting off air flow to tires.

PPV installed backwards No pressure detected at regulator. No air flow through regulator.

Control unit pressure regulator 

mis-set or tampered with

Tire cannot be inflated to target.

Inflate-only system may result in 

frequent condition of tire 

pressure above target 

Depending on extent and duration of over-pressure condition, 

impact could be negligible, or could result in an increased sensitivity 

of the tire to road hazards, degrade tire wear, traction or handling, 

or could contribute to a harsh ride that displaces or damages cargo.

Inflate/Pressure-relief systems 

may result in frequent condition 

of underinflated tires after 

vehicle is parked and tires cool 

down

Depending on extent and duration of under-pressure condition, 

impact could be negligible, or could result in progressive casing 

damage even when the vehicle is parked. In addition, the tire may 

stay underinflated for a longer period after the vehicle begins rolling 

while the system tries to overcome lower pressure induced by ATIS 

pressure relief operation the previous day.

Pressure level to trigger “relief” 

function in Inflate/Pressurerelief systems too close to tire 

target pressure

System simultaneously trying to inflate and exhaust air from tire. For 

systems with a pressure relief function in addition to an inflation 

function, the tire inflation level at which air is vented should be 10 

psi above the target inflation pressure. This also means that tires 

could run in an over-pressure condition for a certain duration before 

the venting function initiates.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 40

Tires are routinely starting up 

underinflated until system 

catches up

May have 10 minutes at start up during which tires are underinflated 

while rolling (in the absence of leaks).

Driver/Operator misinterprets

warning light/system operation 

(or frequent turnover of drivers)

System indicators may be ignored in cases of real low pressure 

conditions.

Technician does not understand 

system operation (or frequent 

turnover of technicians)

Incorrect installation or improper functioning of system.

Component theft Cost to replace system or parts.

Additional maintenance item Include in preventive maintenance (use same schedule as for any 

compressed air system on the vehicle) 3-month, annual checks.

Equipment

Rotary Union worn Air leakage around rotary shaft.

Control Unit malfunction Tire cannot be inflated to target pressure.

Defective pressure or flow 

switch

ATIS is operating but cannot warn driver, as the indicator lamp on 

the front of the trailer will not illuminate.

Length of air lines (distance 

between air tank and hubcap)

Increased line length results in slower inflation rate of tires. 

Insufficient slack can result in line damage due to suspension travel 

or use of sliders.

Grease or oil leaking from hub in 

pressurized axle systems

Too much lubricant in hub. Pressure from axle is leaking to wheel 

end, exceeding hubcap venting capacity. 

Complexity of installation More parts and greater complexity of installation relative to any 

other tire pressure system, excluding CTIS.

Damage

Control Unit or air line damage 

from flying debris

System stops functioning, or may try to operate continuously.

Air line chafing against sharp or 

metal edges

System unable to replenish air to tires, or may allow tire leaks.

Tire hose damaged from contact 

with wheel, stretching, or slack 

allowing hose to extend past 

wheel

System unable to replenish air to tires, or may allow tire leaks.

Air lines pinched or blocked System unable to replenish air to tires.

Contamination

Moist air due to insufficient 

drying or filtering of air at trailer 

air tank

Casing damage or decreased tire life, corrosion.

Ice in system Air flow blocked, can increase moisture content of air supply

Contaminants in system 

components (oil, debris) from 

multiple entry points: hubcap 

vents, axle corrosion or aging, 

improperly installed axle venting

Degraded system performance, deterioration of seals, chemical 

interactions with rubber materials
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 41

Electrical

Corrosion of terminals or 

connectors for trailer indicator 

lamp

Lamp does not function. Driver not warned that system is operating.

Power loss to controller System unable to replenish air to tires, or system operating at 

incorrect level.

Loose wires, electrical shorts Lamp does not function. Driver not warned that system is operating

Bad indicator lamp bulb or LED Lamp does not function. Driver not warned that system is operating

Leaks (most important Risk category)

Air leaks at system connectors, 

fittings

System will try to run continuously. Not able to inflate tire if system 

leak rate exceeds its capacity to supply air.

Check valves in tire hoses or 

hubcap malfunction, are blocked 

or damaged

System will try to run continuously. Not able to isolate tire inflation 

systems from leaking tire.

Leak in tire hoses or at valve 

stem due to interaction with tire 

hose

Tires can deflate when vehicle is parked (system not active, no 

pressure in trailer air tank).

Onerous procedure to check for 

system leaks (soapy water 

solution)

Insufficient technician time to successfully isolate leaking 

component.

(FMCSA, 2003, PressureGuard®, 2013; P.S.ITM, 2006; Hendrickson, 2012; STEMCO, 2012; Interviews with 

industry stakeholders)

3.3.2 ATIS Type 2 – Direct Atmospheric Air Source with Self-Contained Pump

There are two primary strategies for ATIS that use air from the environment surrounding the vehicle 

(ambient or atmospheric air) to re-inflate the tire, with both approaches using the fundamentally similar 

concept of a built-in peristaltic pump. In the first case, a built-in roller in a mechanical unit provides the 

compression that feeds air to the tire. In the second case, the tire itself provides the pumping action. 

The tire must be rolling for either system type to function. ATIS Type 2 products are “distributed” 

systems, meaning that the system is self-contained in the tire or at each wheel end, with multiple units 

on a vehicle. These systems are designed to compensate for the natural loss of tire pressure over time 

due to the diffusion of air through the tire envelope and other slow to moderate leakages. Type 2 ATIS

typically cannot overcome a developing leak at the same level of air loss that can be compensated by 

Type 1 ATI systems.

ATIS Type 2A

A small bolt-on disk assembly is mounted to the hub of each wheel end. Air is drawn into a chamber 

inside the assembly, and is moved through the chamber by an internal roller that compresses the air 

during rotation of the wheels on the vehicle. It is a self-contained mechanical pump with no batteries, 

powered by wheel rotation alone. If the air pressure in the tire is less than the pre-set target of the unit, 

air will move through a tire hose connected from the hub-mounted assembly to the tire valve stem. A 

single unit is mounted on each wheel end, and can accommodate dual or wide-base single tire 

configurations. Units are factory-set to a specific target pressure. If different pressures are needed for 
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 42

drive tires than for trailer tires, separate models should be ordered for each desired target pressure. 

Conceivably, the units can also be used on the steer axle, although there are currently certain wheel end 

packaging challenges associated with the mounting of the disk assembly on this wheel position. A 

potential advantage of this type of system is that it functions fully external to the tire/wheel assembly, 

with the hub bracket and the tire valve stem as the only interfaces.

ATIS Type 2B

As of the writing of this report, no systems of this type were commercially available for heavy-duty truck 

tire applications. ATIS Type 2B is often colloquially referred to as a “self-inflating tire”. This terminology 

is not correct in the strictest sense, but is used because the pumping device that inflates the tire is fully 

contained within the tire itself. In this system a regulator/sensor is installed inside the tire envelope 

with an air tube connection to the valve stem. The air tube itself may be located inside the tire air 

chamber, or may be built into the bead zone as an enclosed ring around the circumference of the tire. 

Each individual system is preset to a target pressure depending on the tire type and vehicle position. 

When an underinflation condition is detected, a modified valve stem opens to allow air from outside the 

tire into the tube. The deformation of the tire during rolling compresses the tube in a pumping motion, 

delivering external air into the tire/wheel assembly. System function is entirely mechanical and is 

installed on each individual tire. This tire technology could be implemented on steer, drive, or trailer 

positions. All ATIS Type 2B products are in prototype or early pre-production phase, and will therefore 

not be considered in later sections of this report.

Details of the operation of ATIS Type 2A and ATIS Type 2B technologies are today relatively strictly 

guarded under intellectual property and trade secret rights. Some fundamentals related to the systems

(but which may not represent final product configurations) are described in the patent literature 

(Renier, 1993; Benedict, 2012; Richardson, 2012).

Overview of Functionality of ATIS Type 2

Tire inflation systems of this type should exhibit the following capabilities, and are generally applicable 

to either Type 2A or Type 2B systems. The relative novelty of these systems may mean that not all 

intended functionality has been deployed as of the time of this study.

 Compensate for the natural tire pressure losses due to air diffusion through the tire body. 

Since this phenomenon is occurring on all tires at the same time, the system must be able to 

supply air to all tires connected to it at this rate.

 Compensate for other conditions of relatively low leak rates such as air losses between the 

tire and the wheel in the bead seat zone, and at improperly tightened or leaking valve stems 

or cores. As above, the system must be able to supply air to all tires connected to it 

simultaneously at this rate.

 Compensate for moderate leaks from small punctures.

 Maintain the tire pressure difference between two tires in a dual assembly to 5 psi or less. 

 Provide clean, moisture-free air supply.

 Prevent contamination of system by oil, dust, moisture, chemicals, or other contaminants.

 Not interfere with existing axle venting, in case of malfunction or overheating of other 

wheel-end components.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 43

 Isolate a rapidly leaking tire from the system, if more than one tire is connected to the same 

unit.

 Because of the relatively lower airflow rates of ATIS Type 2, a visible or audible indicator 

that the system is functioning may be optional.

Focusing on the ATIS Type 2A product category, distinctive features relative to ATIS Type 1 include:

 Quick (< 10 minutes per wheel end), simple installation, using a bracket sized for the wheel 

type and common shop tools.

 Minimum number of system components.

 Does not depend on trailer air tank pressure condition for proper operation. Less loading on 

vehicle compressed air systems that also support other vehicle functions. Self-contained 

system.

 Simpler troubleshooting procedure in event of system leaks.

 Self-powered mechanical system.

 Can be easily applied to drive axles as well as trailer axles.

 Lower airflow rates less likely to result in tire over-pressure condition.

Potential Risks Related to ATIS Type 2A

As indicated in the earlier discussion of ATIS Type 1 risks, there is always the possibility that a given risk 

may occur. However, it is also possible that the risks listed below will not occur at all, or occur only with 

very low frequency. In any case, fleet management should execute a risk analysis and develop at least a 

basic risk response plan before investing in extensive system installation. 

Risks are divided into the following categories: Operations, Equipment, Damage, Contamination, and 

Leakage. (Electrical not applicable.)

Exhibit 3.10 Potential Risks Associated with Use of ATIS Type 2A – Direct Atmospheric Air Source

RISK IMPACT

Operations (interactions between tire pressure systems and fleet operations)

Steer tires not managed by 

automatic tire inflation system

System (hub-attached) components currently are not optimized for 

mounting on steer axle positions.

Tires routinely start up 

underinflated until system 

catches up

May have indeterminate period at vehicle start-up during which tires 

are underinflated while rolling (in the absence of leaks).

Inflate-only system may result in 

frequent condition of tire 

pressure above target. No 

pressure relief or venting 

function for tires.

Depending on extent and duration of over-pressure condition, 

impact could be negligible, or could result in the increased sensitivity 

of the tire to road hazards, degraded tire wear, traction or handling, 

or a harsh ride that displaces or damages cargo.

User cannot adjust target 

inflation pressure after system 

implementation.

Requires the purchase of additional systems tuned to new target 

pressure. For certain systems, it may be possible for the supplier to 

make adjustments on a case-by-case basis.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 44

System does not alert user when 

operating.

Abnormal leak condition of tire not recognized / repaired.

System does not alert user when 

malfunctioning.

Tires cannot be inflated to target. User unaware of system fault 

condition. 

Component theft Cost to replace system or parts.

Additional maintenance item Current limited experience with systems in the field. However, due 

to the self-containment and simplicity of ATIS Type 2A systems, 

maintenance requirements are expected to be lower for this system 

type.

Equipment

Control Unit malfunction Tire cannot be inflated to target pressure.

Long term system durability and 

reliability

New technology, limited field exposure. 

Damage

Tire hose damaged from contact 

with wheel, stretching, or slack 

allowing hose to extend past 

wheel

System unable to replenish air to tires, or may allow tire leaks.

Contamination

Moist air due to insufficient 

drying or filtering of air at inlet 

to system

Casing damage or decreased tire life, corrosion.

Ice in system Air flow blocked, can increase moisture content of air supply

Contaminants in system 

components (oil, dust, debris)

Degraded system performance, blocked air flow, chemical 

interactions with rubber materials if contaminants enter tire 

envelope.

Leaks (most important Risk category)

Tire leak exceeds system 

capacity to re-inflate, e.g. leaks 

greater than natural loss cannot 

be compensated

Tire cannot be inflated to target pressure and progressively loses air.

Air leaks at system connectors, 

fittings

System will try to run continuously. Not able to inflate tire if system 

leak rate exceeds its capacity to supply air.

Check valves in tire hoses 

malfunction, are blocked or 

damaged

System will try to run continuously. Not able to isolate tire inflation 

systems from leaking tire.

Leak in tire hoses or at valve 

stem due to interaction with tire 

hose

Tires can deflate when vehicle is parked (system not active)

(Peo, 1936; Renier, 1993; Renier, 1993a; Olney, 1994; Benedict, 2012; Interviews with system suppliers;

CODA, 2008)
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 45

3.4 Central Tire Inflation Systems (CTIS)

Like ATIS, Central Tire Inflation Systems (CTIS) use air from the vehicle’s compressed air system to inflate 

the tires, normally from the vehicle’s air brake tank. The components used in these systems are sensors, 

manifolds, hoses and valves, harnesses, and the controller/display. In contrast to ATIS, a CTIS set-up 

includes an ECU in addition to an air regulating system. The vehicle operator has the ability to change 

the target pressure of the tires from inside the cab, on demand, in response to changes in road or 

environmental conditions. The ECU controls the signaling to the pneumatic system to inflate or deflate 

the tires. Air is also delivered to maintain a constant target pressure. CTIS systems are most often found 

in off-road applications characterized by uneven terrain and costly vehicle equipment, including mining, 

logging, construction and military operations.

Potential risks associated with the use of CTIS are categorized into equipment, leaks, and damage. The 

slip ring seal that is part of the manifold on the end of the axle could become worn over time due to the 

rotating hub. The system may cover up a slow leak that is occurring, for example a nail in the tread of 

the tire. Over time, undetected slow leaks will potentially cause more damage to the tire. Road debris 

and normal wear may also contribute to damage of the rotary union and the hoses that could inhibit the 

correct amount of airflow to inflate the tires.

3.5 Passive Pressure Containment Approaches

Additional tire pressure product categories offer ways to maintain air in the tire without any action to 

measure, report, or adjust inflation pressure once a tire has been aired up. Nitrogen inflation attempts 

to reduce natural pressure losses due to diffusion through the casing. Use of tire sealants, in several 

forms, is generally aimed at downtime reduction due to air loss caused by small punctures.

3.5.1 Nitrogen Inflation

Naturally occurring atmospheric air – the air we breathe – is made up of approximately 78% nitrogen, 

21% oxygen, and 1% other gases and includes water vapor. Normally, this is the mixture of the air that 

is put into tires. A shop system may include a dryer in order to reduce the amount of water vapor in the 

ambient air supply, decreasing the amount of moisture going into the tire/wheel assembly. 

Use of concentrated nitrogen instead of atmospheric air slows down the natural pressure loss in tires. 

Suppliers of nitrogen systems typically use a membrane process to remove oxygen and moisture from 

the air, taking advantage of faster permeation rates of these components relative to nitrogen. High 

concentration nitrogen gas is then collected in a pressurized storage tank. Generally, the percent 

nitrogen in the tank is about 95% or higher. The same permeation properties that slow the diffusion of 

nitrogen in commercial nitrogen generator systems help keep air in the tire once it has been inflated. 

Laboratory tests comparing tires inflated with atmospheric air versus tires inflated with high 

concentration nitrogen have shown that nitrogen inflation can reduce natural pressure losses (Evans, 

2009; Park 2011). However, it should be noted that the measured pressure losses are small in both 

cases. In the absence of other sources of leaks or air seepage, a tire inflated with nitrogen will hold its 

original pressure longer than one filled with standard air. 
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 46

Due to the inert nature of nitrogen, tire manufacturers generally concur that the use of high 

concentration nitrogen as an inflation medium will not have adverse effects on tire inner liners or on tire 

performance during normal operations. A good tire pressure maintenance program is still needed to 

detect and prevent air loss from other sources such as leaking valve stems or poor bead seating, which 

cannot be compensated by nitrogen inflation. 

Other considerations for the use of nitrogen inflation in long haul commercial vehicle applications

include:

 Procedures must be established for any time the tires might need additional air when away 

from maintenance centers and a source of high concentration nitrogen may not be 

available.

 Dry air is a key element for good results with nitrogen inflation (or in fact, for any 

compressed air system). Moisture in any air source can promote corrosion or degradation 

of tires and wheels. The use of dry air can also reduce pressure variations due to the 

response of water vapor to temperature changes (either external temperature or tire 

operating temperature). 

 Remember that natural pressure losses can be slowed, but not completely prevented, with 

nitrogen inflation. Over time, if a normally maintained tire inflated with standard air is not 

punctured or deflated, the concentration of nitrogen (but not the total amount of air) will 

gradually increase, and may reach as much as 2%-10% higher concentration of nitrogen than 

found in atmospheric air. In addition, particularly with highest purity nitrogen (~98% and 

above), small quantities of oxygen diffuse back into the tire envelope from the surrounding 

environment, although in smaller concentration than in standard air. 

 Current automatic tire inflation systems use the trailer air tank or air from surrounding 

environment as an air source, and will over time return any initial inflation using high 

concentration nitrogen to standard air nitrogen concentrations.

3.5.2 Tires with Built-in Sealant Layer

In recent years, certain tire lines containing a built-in sealant layer have been developed and 

commercialized for heavy truck applications. The sealant layer is built into the tire between the inner 

liner and casing ply as part of the normal manufacturing process. During curing, the sealant takes on a 

gel-like consistency that enables it to flow in the finished tire. For example, if a nail penetrates the tread 

and the sealant layer, the sealant immediately sticks to the nail and surrounds the area around it, 

sealing the leak. If the nail is pulled out, sealant is pulled into the puncture area and seals the hole. 

Positioning the sealant layer between components of the tire construction maintains even distribution 

of sealant around the tire circumference.

In current configurations, sealant is present only in the tread area of the tire, covering the repairable 

zone of the tire and also the zone in which most punctures occur. Multiple punctures of up to 1⁄4” 

diameter can be sealed with high reliability, and the product may be effective in repairing damage from 

larger obstacles. 

Because sealant has been directly incorporated into the conception of the tire, products with built-in 

sealant perform with known and controlled properties. They are compatible with normal retread 
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 47

processes and are designed to undergo multiple retreading. Sealant is not removed or added during 

retreading. Sealant tires in this category are covered by the same warranty as the equivalent tire model 

without sealant.

For long haul applications, sealant tires are available in wide base single drive and trailer, and in dual 

trailer fuel-efficient models. The sealant layer can add 8-10 pounds to total tire weight compared to a 

non-sealant version. 

Built-in sealant cannot compensate for natural pressure losses, or for leaks or seepage unrelated to 

tread punctures. Sealant tires can reduce emergency downtime expenses by allowing the tire to 

maintain pressure at or near its original level until repairs can be made. However, a fleet using sealant 

tires could potentially run long periods with nails in a tire and not know it, because the tire has not lost 

air. It is recommended that fleets look for damages to the tread during their routine inspections, and 

also during weekly tire inflation pressure checks.

A potentially interesting assembly of pressure technologies could be to combine tires with built-in 

sealant – to protect against pressure loss due to road hazards – with an automatic tire inflation system 

tuned to compensate low volume pressure loss due to natural diffusion of air through the casing.

3.5.3 Aftermarket Sealants

Aftermarket sealants are coatings that are applied to the inside of the tire casing as part of the tire 

mounting process, either by a fleet’s own maintenance shop or by a tire service provider. There is a very 

broad range of aftermarket sealant products, suppliers, and applications in the market. Sealants of this 

type have historically been used in agricultural, construction, mining and off-road applications in which 

tires are routinely subjected to road hazards. More recently, aftermarket sealants have undergone

progressive updates to provide products that are better adapted to the use and life-cycles of highwayspeed, heavy duty vehicle tires. 

In general, aftermarket sealants are composed of some type of fibers and/or fillers in a thick liquid 

suspension. Fibers may be textile filaments or of other composition. Fillers can include small particles 

of crushed rubber or plastics. Sealant performance depends on its compounding properties, and each 

supplier creates a specific formulation to adapt the product to a particular usage.

Although different suppliers may recommend different practices for sealant application, aftermarket 

sealants are usually injected before the beads are seated through the valve stem with the valve core 

removed using a hand pump. In some cases, sealant can be injected into fully mounted and inflated 

tires using a pneumatic pump system. Manufacturers have generated tables that indicate the amount 

of sealant, or “dosage”, needed depending on the tire size. For typical highway tires in sizes such as 11 

R22.5, 275/80 R22.5 or 295/75 R22.5, the dosage ranges from about 36-50 fluid ounces, or 

approximately 3-5 pounds per tire for the initial dose. After injection, it is estimated that the sealant 

spreads to cover the full inner liner of the tire (tread and sidewall area) within about the first hour of 

rolling. Additional sealant may need to be added during normal use of the tire.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 48

Aftermarket sealants may offer an additional barrier against natural pressure losses due to air migration 

through the casing, as well as providing an immediate seal around punctures. Certain products may not 

be capable of sealing punctures, but provide a barrier layer to air permeation only. Products that are 

designed to seal punctures advertise the ability to reliably treat punctures in the range of 1⁄4” to 1⁄2”. 

Tire warranties will typically remain in effect if the sealant provider has tested and certified use of the 

sealant in tires. However, if the sealant is judged to be the cause of damage to the inner liner or to have 

degraded tire performance, the warranty may be voided. Fleets should ask sealant and tire suppliers 

about potential warranty concerns in advance.

Because of the variations in the chemical nature of aftermarket sealants across the wide array of 

products, and because the sealant has not been an integral part of tire or rim design and development, 

caution should be taken to ensure that any selected aftermarket sealant:

 Is chemically compatible with tires, wheels, and any components that may come in contact 

with the sealant.

 Is approved for speeds associated with highway use and with the speed rating of the tire.

 Is compatible with retreading processes. Normally, sealant must be thoroughly cleaned 

from the tire casing before retreading. In some cases, sealant residue may be flammable at 

retreading temperatures.

 Will perform properly over the range of warm and cold temperatures normally experienced 

during vehicle operation.

Aftermarket sealant suppliers should clearly state any incompatibilities between their products and 

active tire pressure systems such as TPMS, ATIS, and dual tire equalizers. Fleet users are encouraged to 

comprehensively review with these suppliers any risks or concerns they may have if combining 

electronic or automatic tire pressure systems with specific aftermarket sealants.

4.0 Original Equipment Manufacturers’ Perspectives on Tire Pressure System Integration

The NACFE study team interviewed various trailer and tractor builders during the course of the project 

to gain insights into their experience working with end user fleets and the tire pressure systems 

suppliers.

4.1 Trailer OEMs

Several trailer OEMs were interviewed who supply different types of trailers including dry van, 

refrigerated, pup trailers, tankers, flatbeds, dumps and other specialty vocations. Their comments are 

summarized here.

 The procurement of tire pressure systems on newly purchased equipment is growing;

approximately 40% of all new trailers built have systems.

 For trailers equipped with tire pressure systems, ATIS are more common than TPMS by a 

ratio of about four to one. Responses ranged from 10–40% for new trailers built in 2013 

with ATIS and 5–15% with TPMS.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 49

 Increasingly, fleet customers are asking the trailer builders about tire pressure systems. One 

trailer OEM mentioned that they have now hired an internal sales representative for tire 

pressure systems, and most stated that they are getting sales, assembly and maintenance 

training from the system suppliers to better support their customers.

 In some cases, trailer manufacturers are assisting the fleets in their retrofit actions.

 Axles are being supplied already drilled and tapped to the trailer assembly facilities to better 

accommodate integration of the tire pressure systems on the production lines.

4.2 Tractor OEMs

The NACFE team met with tractor builders over the course of the project and received the following 

insights:

 Tire pressure is important on tractors as well as on trailers, but tractor builders reiterated 

the belief that tire pressure is better maintained on tractors than on trailers.

 One tire pressure monitoring system is production-available at three of the OEMs, with 

somewhat limited adoption. It was shared that the system’s payback, even with the higher 

relative miles driven on the tractor, is not yet sufficient to generate significant demand.

 Other manufacturers’ products are available on new equipment via new truck upfitters or 

dealers prior to delivery of the equipment to the purchaser.

 Multiple tractor OEMs shared that they would be willing to engineer various TPMS into their 

tractors for a reasonable order volume and a few also shared that they are conducting 

internal studies in order to offer these systems as regular production. This approach could 

lead to reduced cost for purchasers of tire pressure systems as the components would be 

integrated in the truck, thus avoiding the upfit costs. 

5.0 Summary of Fleet Perspectives and Experiences with Current Tire Pressure Systems

Class 8 over the road tractor-trailers are characterized by high miles driven delivering goods such as 

consumer products in dry van or refrigerated trailers, bulk materials via tankers, freight on flatbeds, etc. 

There are approximately 1.8 million of these vehicles in the United States and they represent a majority 

of the fuel used in ground transport and consequently, also consume large quantities of tires. 

The value of appropriate tire pressure is significant and becomes increasingly so with higher fuel and tire 

prices. As fleets are actively pursuing efforts to lower their operating costs, manufacturers are 

responding with technologies that ensure good pressure levels in the tires of Class 8 trucks. Fleets are 

also realizing that their tire pressure maintenance practices, which at present primarily consist of having 

drivers manually check tire pressure at all wheel ends, are not sufficient to keep the tires at the 

appropriate pressure. 

The fleets shared with NACFE that they recognize the benefits of proper tire pressure and are 

considering the adoption of technologies that can better ensure it. Conversations typically centered 

around three primary benefits:
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 50

1. Improved safety and fewer roadside breakdowns. Very low tire pressure, which can result 

from decreasing air in the tire left unattended, can cause a tire rupture and potentially a 

vehicle accident. At a minimum, it can create a roadside breakdown, causing downtime and 

cost for a service vehicle to come to the tractor-trailer and replace the tire.

2. Decreased tire life. Operating on low tire pressure causes premature wear of the tire 

leading to an earlier than expected or needed replacement of the tire.

3. Lower fuel economy. Driving the tire on lower tire pressure increases its rolling resistance 

and penalizes fuel economy. 

For fleets to properly evaluate the effect of low tire pressure on their operating costs and in turn 

appropriately value the use of a new technology, the fleet should understand the true costs of the items 

above. These cost elements are prioritized in the order listed above, as fleets, in general, shared the 

potential benefits of tire pressure systems in this order and generally justified adoption of technologies 

by identifying improvements in costs in these three categories.

Fleets also shared that tire pressure systems can offer enough value to consider retrofitting them on 

tractors and/or trailers, where there is enough life left on the equipment to justify doing so. Private 

fleets generally keep their equipment much longer than their for-hire counterparts, who generally sell

equipment after four to six years of long-haul use. Also, trailers are much more often candidates for 

retrofitting, as all fleets tend to keep trailers for most, if not all of their useful life. Retrofitting also has 

the cost of taking the equipment out of service in order to add the aftermarket components, requiring a 

longer and costlier labor process - about twice as much cost as if the device was procured on the original 

equipment.

The team concluded that there are some early adopters of tire pressure systems. They include, but are 

not limited to:

 Tankers, and in particular, those hauling hazardous materials where the gravity of a vehicle 

accident can be severe.

 Vehicles with high trailer miles and/or low trailer to tractor ratios, for instance, refrigerated 

units, where the benefits of proper tire inflation are further amplified with the higher miles. 

 Duty cycles with diminishing loads, where the diversity of fully-loaded and empty trailers cause 

tire wear problems and where consistent, sufficient tire pressure can help.

System Selection

Reliability

Universally fleets shared that the number one criteria for tire pressure system selection is reliability. 

The equipment simply must not have downtime, as the efficiency of down equipment is zero. Factors 

such as the variation of available system designs from monitoring to inflation, sensors inside the tire

versus outside, vehicle supplied inflation air versus direct atmospheric air supply, provides difficult 

challenges for fleets in selecting the appropriate system for their use. There is much improved 

confidence in the current systems in comparison with earlier versions where problems with sensor 

reliability and durability and component robustness against harsh environments, such as de-icing road 

chemicals, were more common.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 51

For-Hire versus Private Fleets

During the course of the analysis of data collected from the fleets, it was noticed that for-hire trucking 

firms (fleets who were hired to haul freight for others), tended to adopt or study to adopt, tire inflation 

systems more often than their private carrier counterparts. Private carriers are fleets that manufacture 

and or distribute their goods using their own transportation equipment. This conclusion was clearly not 

universal, but evident. Numerous fleets, both for-hire and private, mentioned that their choice of 

system was often contingent upon their drivers. For-hire fleets tended to more highly value systems 

that did not require interaction from the driver (automatic tire inflation) while the private carriers 

wanted to better engage the driver in fixing the inflation problem (tire pressure monitoring). This seems 

to be due to the fact that there is much shorter tenure of truck drivers in the for-hire group than in the 

private carrier group. See Exhibits 5.1 and 5.2 below for driver turnover, using the same scale for these 

two groups.

For-hire truck drivers are less experienced and move from one company to another five times more 

frequently than drivers employed by private fleets. Those buying and operating these fleets therefore

seem to tend towards the less driver-intensive systems of automatic tire inflation. Private carriers’ 

drivers are more tenured and those fleets seem to be choosing tire pressure monitoring systems more 

frequently, as they are generally less expensive to procure and deliver more information via data 

collection and telematics to the fleet management for action and analysis.

Exhibit 5.1 Historical Rates of For-Hire Truckload Carrier Driver Turnover 2005-2012

(ATA, 2013)

2005 2006 2007 2008 2009 2010 2011 2012

0

20

40

60

80

100

120

140

160

Percent Turnover

Large TL Turnover Small TL Turnover

ATA: For-Hire TL Carrier Driver Turnover

2005 - 2012 Q4

American Trucking Associations, ACT Research Co., LLC: Copyright 2013
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 52

Exhibit 5.2 Historical Rates of Private Carrier Driver Turnover 2005-2012

(NPTC, 2013)

Payback Calculations

The NACFE interviewers asked the fleets how they calculate the payback for a particular tire pressure 

system implementation in order to make their decisions. The answers were very inconsistent. All 

included both the cost of the hardware and the installation labor cost, either as new production or 

retrofit, into their calculations. Fleets also commonly acknowledged the benefits of increasing safety 

and lowering roadside breakdowns, improved tire wear and lower fuel consumption, but did not use all 

three of these generally in their analyses. Roadside breakdowns were the most commonly included 

justification with tire wear second and fuel economy last. Fleets shared that tire wear and fuel economy 

improvements could be attributed to other actions rather than just the tire pressure system adoption. 

NACFE has created a payback calculator with this report that is described later in this document.

Other Findings Concerning Technology Selection

As stated earlier, fleets have a number of choices for systems that will lower their expenses by 

optimizing tire inflation levels. Through analysis of the data supplied by fleets in the Internet survey, 

meetings and discussions at trucking events, the following findings emerged:

 There is a higher adoption of tire pressure systems by fleets that have decided to use wide 

base tires on their equipment. Wide base tires use one wider tire per wheel-end rather than 

the traditional duals. The consequence of a tire failure can be more severe in this case as 

wheel damage may occur with a tire blowout, or possibly due to extreme underinflation. A 

few fleets mentioned that they believed it was mandatory to have a tire pressure system 

with wide base tires, although this is not the case currently. No tire manufacturer requires 

the use of tire pressure systems, but they may be recommended by a few OEMs.

20052006200720082009201020112012

0

20

40

60

80

100

120

140

160

Percent Turnover

NPTC Benchmark Survey: 

Private Fleet Driver Turnover

2005 - 2012

National Private Truck Council, ACT Research Co., LLC: Copyright 2013
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 53

 Some fleets want to have tire pressure systems on both their tractors and trailers. These 

include owner-operators who own both the tractor and the trailer and tend to always keep 

them connected as well as fleets that operate much the same way. In these cases, fleets 

tend to prefer tire pressure monitoring systems that allow for a common system across both

tractor and trailer with the same in-cab communication displays and common telematics 

data acquisition.

 The average trailer-to-tractor ratio for fleets in the Unites States is around 3:1 (NACFE Study 

fleets reported 3.1:1 in 2013) and can range from a low of around 1.3:1 for refrigerated 

fleets to over 10:1 for specialty business model situations. Therefore, trailers tend to only 

be “attached” to a tractor for weeks or even only days at a time, creating a lack of attention 

to trailer maintenance by many drivers. This situation tends to encourage fleets to consider 

tire pressure inflation systems that will help ensure appropriate tire pressure if trailers are 

away from terminals or maintenance centers for an extended period of time, or simply do 

not get the regular tire pressure checks that tractor tires often receive.

 For fleets that are data-driven and who want to understand the tire pressure details for 

different tire positions, on various equipment types, and when driving diverse routes, TPMS

can be the option where the data available for that analysis can be easily communicated, 

logged and sent to the appropriate resource for analysis. 

 With respect to tractors, a number of fleets shared that they would really like to have the 

option of ATIS on them. Central tire inflation systems are currently available for military and 

off-road use, but are not cost competitive for Class 8 over-the-road trucking. An emerging 

cost-effective solution is the ATIS Type 2 equipment for tractors.

 Fleets see several new features emerging that are very helpful in their expense 

management. They shared that these include such items as:

o Drop-and-hook feature that allows different tractors and trailers to use a 

common system when moving from different equipment.

o Warning lights at the wheel end, for instance a green indicator light when 

pressure is acceptable, yellow if it is somewhat low and red if seriously low, 

in addition to in-cab reporting.

o Managed pressure relief of tires by ATIS if an increase in ambient 

temperature drives up the tire pressure.

6.0 Tools – Technology Decision Matrix and Payback Calculator

NACFE has created two tools for the industry based on what we have learned from this study: a 

technology decision matrix and a payback calculator. Both tools are available as a download from the 

NACFE website. 

6.1 Technology Decision Matrix

This tool identifies the major characteristics of the various Tire Pressure Technology System types in a 

single chart, shown in Exhibit 6.1. End users, tire pressure systems manufacturers, tractor and trailer 

builders and others can use filters to highlight specific systems of interest in order to better compare the 

attributes of the various technologies. This tool is meant to condense the immense amount of 
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 54

information obtained during this study effort into a single matrix that can assist in the selection of 

various technology types for specific fleet duty cycles and business models. The complete Decision 

Matrix can be obtained from the NACFE website; Exhibit 6.1 presents only a small extract of the 

information contained in the full matrix.

Exhibit 6.1 NACFE Tire Pressure System Technology Decision Matrix (small extract of data included here)

6.2 Payback Calculator

Fleets, manufacturers and others can input data and estimate the payback of certain technologies given 

the benefits described throughout this report. The calculator uses data from various published sources, 

including the Federal Motor Carrier Safety Administration, the Technology and Maintenance Council, 

tire manufacturers, fleets, the tire pressure systems suppliers, tractor and trailer manufacturers and 

others. It calculates a simple payback in terms of roadside breakdowns, tire wear and fuel economy cost

reductions given the use of the vehicles and data supplied by the fleet. Users may evaluate tractor-only, 

trailer-only, and tractor-plus-trailer fitments. It is a balanced and straightforward tool to be used by 

stakeholders in the industry to show the general economics for tire pressure system adoption. 

Exhibit 6.2 shows a calculation output from the payback calculator. Users input their specific data, such 

as the number of tractors and trailers in the fleet, the number that will have TPS equipped and 

acquisition and installation cost of the system into the yellow boxes. Default values are provided and 

sources shown as noted below the calculator. Two of the boxes provide drop-down menus for users to 

input the effectiveness of their current tire pressure practices and the ability of the Tire Pressure System 

to detect problems. Then the tool calculates the quantifiable benefits from the system with respect to 

savings of reduced roadside breakdowns, extended tire wear and improved fuel economy for tractor 

and/or trailers equipped with these devices. Exhibit 6.2 presents example results for an owner-operator 

end-user with one tractor and a single trailer, providing a payback in less than 18 months.

©2013	North	American	Council	for	Freight	Efficiency.	All	rights	reserved.

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and	NACFE	assumes	no	liability	for	use	of	the	report	contents.	No	portion	of	this	report	or	accompanying	materials	may	be	copied,	reproduced	

or	distributed	in	any	manner	without	express	attribution	to	the	North	American	Council	for	Freight	Efficiency.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 55

Exhibit 6.2 NACFE Tire Pressure Payback Calculator – Owner-Operator

Yellow	boxes	are	for	user	inputs

Tractors Trailers Notes:

Number	of	Tractors 	 1 Fleet	Input

Number	of	Trailers 	 1 Fleet	Input

Miles	per	year 	 100,000 	 100,000 Fleet	Input	&	Calculated

Effectiveness	of	Fleet's	tire	pressure	practices good good Fleet	Estimate	

Vehicle	average	underinflation 10% 10% Calculated

Cost	of	Tire	Pressure	System $	 750 $	 475 NACFE	Est.	-	See	Source	1.

Installation	Cost	(particularly	if	retrofit)

Total	Installed	Cost $	 750 $	 475 Calculated

Equipment	with	TPS 	 1 	 1 Fleet	Input

Total	Installed	Cost $	 750 $	 475 Calculated

Benefits

Roadside	Breakdowns	due	to	low	pressure

Tire	Related	Breakdowns/	Truck	/	Year 1 1 From	NACFE	Fleet	Survey

Avg	cost	/	breakdown	including	tire	cost $	 500 $	 500 From	NACFE	Fleet	Survey

%	Effectiveness	of	TPS	to	detect 70% 80% Fleet	Estimate

Benefit	from	reduced	breakdowns $	 350 $	 400 Calculated

Tire	Wear

Improvement	in	tire	life 4% 4% Sources	2.	and	3.	below

Tire	cost	per	mile $	 0.021 $	 0.021 Source	5	ATRI	=	$0.042/mile

Improved	cost	per	mile $	 0.001 $	 0.001 Calculated

Benefit	from	tire	wear $	 84 $	 84 Calculated

Fuel	Economy

Improvement	in	Fuel	Efficiency 0.75% 0.75% Sources	2.,	3.	and	4.	below

Fuel	cost	per	mile $	 0.295 $	 0.295 Source	5	ATRI	=	$0.590/mile

Improved	cost	per	mile $	 0.002 $	 0.002 Calculated

Benefit	from	fuel	economy $	 221 $	 221 Calculated

Total	of	all	Benefits $	 655 $	 705 Calculated

Payback	in	months 13.74 8.08 Calculated

Sources:

3.	Goodyear	"Radial	Truck	Tire	and	Retread	Service	Manual",	2003,	p.40

4.	Bridgestone	"Real	Answers,	Tires	and	Truck	Fuel	Economy",	2008,	p.25

NACFE	Study	Payback	Calculator:	Tire	Pressure	Systems

©2013	North	American	Council	for	Freight	Efficiency.	All	rights	reserved.

The	contents	of	this	document	are	provided	for	informational	purposes	only	and	do	not	constitute	an	endorsement	of	any	product,	service,	

service	provider,	manufacturer,	or	manufacturing	process.	Nothing	contained	herein	is	intended	to	constitute	legal,	tax,	or	accounting	advice,	

and	NACFE	assumes	no	liability	for	use	of	the	report	contents.	No	portion	of	this	report	or	accompanying	materials	may	be	copied,	reproduced	

or	distributed	in	any	manner	without	express	attribution	to	the	North	American	Council	for	Freight	Efficiency.

5.	American	Transportation	Research	Institute,	“An	Analysis	of	the	Operational	Costs	of	Trucking:	A	2012	Update”,	September	2012.	Tire	cost	

per	mile	=	$0.042;	Fuel	cost	per	mile	-	$0.59

1.	An	aggregation	of	NACFE	Study	interviews	-	ATIS	=	$1,000,	TPMS	=	$750	for	intial	tractor	or	trailer	unit	and	an	additional	$475	to	add	an	

attaching	tractor	or	trailer	to	the	first	TPMS.

2.	Technology	&	Maintenance	Council,	Recommended	Practice	RP	235,	“Guidelines	for	Tire	Inflation	Pressure	Maintenance”,	American	Trucking	

Associations,	Arlington,	VA.,	2012.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 56

7.0 Fleet Case Studies

Two case studies of tire pressure system adoption are presented below. The first describes the adoption 

of automatic tire inflation systems (ATIS) on trailers by a for-hire fleet and the second, tire pressure 

monitoring (TPMS) for both tractors and trailers by a private carrier. These case studies are 

representative of a number of fleets that were interviewed by the study team and are a consolidation of 

their experiences. They are not actual examples of any one fleet’s experiences, but are characteristic of 

real fleet operations and provide helpful information for those considering the purchase and use of tire 

pressure systems.

7.1 Case Study 1: For-Hire Fleet Adopts ATIS for Trailers

This fleet is a large carrier in the business of moving truckload freight across the country. They are 

typical of other large, for-hire fleets and have about 5,000 tractors and 15,000 trailers. Their tractors 

average about 124,000 miles per year and their 3-to-1 trailer-to-tractor ratio results in trailers averaging

about 41,000 miles per year. Fleet long-haul operations require their drivers to be on the road for up to 

three weeks at a time, driving and living in their sleeper tractors, and driver turnover is high. This fleet’s 

turnover is slightly better than the industry average but ranges from 85% to over 100%. 

Trailers are often “dropped” at sites away from fleet terminals and maintenance centers, with other 

trailers being picked up by the fleet’s tractors and drivers. Given the level of driver turnover and the 

limited amount of time that a driver is pulling any particular trailer, the fleet was concerned about 

adding any tire pressure technology that requires greater engagement and involvement by the driver. 

Therefore, when this fleet investigated tire pressure systems, they preferred automatic tire inflation 

systems as a technology choice. As various solutions were investigated, they developed a payback 

calculator and determined through analysis and preliminary testing that they could substantially 

improve their tire wear with ATIS on their trailers. After extended analysis, they decided to order ATIS 

on 100% of their new trailer purchases beginning in 2012 and to retrofit the system on all trailers that 

were nine years old or newer. The payback calculation delivered a return on their investment in 

approximately one year. Due to the large volume purchase of systems, they were able to receive a 

discounted unit cost that significantly helped the payback computation. The retrofit option where the 

ATIS is installed by the trailer dealership or fleet maintenance location added about $110 to the total 

installed cost versus the OEM installation as part of the new trailer delivery. 

After making the decision to install ATIS, the fleet decided to conduct a fuel efficiency comparison of 

about 60 trucks pulling trailers without tire inflation systems to 75 trucks matched with trailers with the 

system. The test period ran for four months from March through June 2012, and demonstrated that 

combination vehicles using trailers equipped with ATIS showed an average improvement of 1.5% miles 

per gallon compared to those vehicles without the systems. To date, there has not been any reliability 

or durability issues with the product, but the fleet warns that it might be too early to tell.

Finally, this fleet has decided not to pursue TPMS for their tractors and is expanding their training for 

manual pressure checking of tires by drivers and maintenance technicians to ensure the right tire 

pressure on all tractor tires. Use of TPMS or new ATIS technology for their tractors will be evaluated at a 

later date. The fleet mentioned that they have been following the developments of ATIS Type 2A, 
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 57

described in Chapter 3 of this report, as a potential cost-effective tractor solution. Payback results using 

this fleet’s data in the NACFE tire pressure payback calculator are as shown in Exhibit 7.1 below.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 58

Exhibit 7.1 NACFE Tire Pressure Payback Calculator – For-Hire Fleet with Trailer ATIS

Yellow	boxes	are	for	user	inputs

Tractors Trailers Notes:

Number	of	Tractors 	 5,000 Fleet	Input

Number	of	Trailers 	 15,000 Fleet	Input

Miles	per	year 	 124,000 	 41,333 Fleet	Input	&	Calculated

Effectiveness	of	Fleet's	tire	pressure	practices good deficient Fleet	Estimate	

Vehicle	average	underinflation 10% 20% Calculated

Cost	of	Tire	Pressure	System $	 - $	 750 NACFE	Est.	-	See	Source	1.

Installation	Cost	(particularly	if	retrofit)

Total	Installed	Cost $	 - $	 750 Calculated

Equipment	with	TPS 	 - 	 10,000 Fleet	Input

Total	Installed	Cost $	 - $	 7,500,000 Calculated

Benefits

Roadside	Breakdowns	due	to	low	pressure

Tire	Related	Breakdowns/	Truck	/	Year 1 1 From	NACFE	Fleet	Survey

Avg	cost	/	breakdown	including	tire	cost $	 500 $	 500 From	NACFE	Fleet	Survey

%	Effectiveness	of	TPS	to	detect 80% 80% Fleet	Estimate

Benefit	from	reduced	breakdowns $	 - $	 4,000,000 Calculated

Tire	Wear

Improvement	in	tire	life 4% 16% Sources	2.	and	3.	below

Tire	cost	per	mile $	 0.021 $	 0.021 Source	5	ATRI	=	$0.042/mile

Improved	cost	per	mile $	 0.001 $	 0.003 Calculated

Benefit	from	tire	wear $	 - $	 1,388,800 Calculated

Fuel	Economy

Improvement	in	Fuel	Efficiency 0.75% 1.50% Sources	2.,	3.	and	4.	below

Fuel	cost	per	mile $	 0.295 $	 0.295 Source	5	ATRI	=	$0.590/mile

Improved	cost	per	mile $	 0.002 $	 0.004 Calculated

Benefit	from	fuel	economy $	 - $	 1,829,000 Calculated

Total	of	all	Benefits $	 - $	 7,217,800 Calculated

Payback	in	months n/a 12.47 Calculated

Sources:

3.	Goodyear	"Radial	Truck	Tire	and	Retread	Service	Manual",	2003,	p.40

4.	Bridgestone	"Real	Answers,	Tires	and	Truck	Fuel	Economy",	2008,	p.25

NACFE	Study	Payback	Calculator:	Tire	Pressure	Systems

2.	Technology	&	Maintenance	Council,	Recommended	Practice	RP	235,	“Guidelines	for	Tire	Inflation	Pressure	Maintenance”,	American	Trucking	

Associations,	Arlington,	VA.,	2012.

1.	An	aggregation	of	NACFE	Study	interviews	-	ATIS	=	$1,000,	TPMS	=	$750	for	intial	tractor	or	trailer	unit	and	an	additional	$475	to	add	an	

attaching	tractor	or	trailer	to	the	first	TPMS.

5.	American	Transportation	Research	Institute,	“An	Analysis	of	the	Operational	Costs	of	Trucking:	A	2012	Update”,	September	2012.	Tire	cost	

per	mile	=	$0.042;	Fuel	cost	per	mile	-	$0.59

©2013	North	American	Council	for	Freight	Efficiency.	All	rights	reserved.

The	contents	of	this	document	are	provided	for	informational	purposes	only	and	do	not	constitute	an	endorsement	of	any	product,	service,	

service	provider,	manufacturer,	or	manufacturing	process.	Nothing	contained	herein	is	intended	to	constitute	legal,	tax,	or	accounting	advice,	

and	NACFE	assumes	no	liability	for	use	of	the	report	contents.	No	portion	of	this	report	or	accompanying	materials	may	be	copied,	reproduced	

or	distributed	in	any	manner	without	express	attribution	to	the	North	American	Council	for	Freight	Efficiency.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 59

7.2 Case Study 2: Private Carrier Adopts TPMS for Tractor and Trailer

As described in the fleet perspectives section of this report, private carriers have significantly lower 

driver turnover than for-hire fleets. It is common for private fleets to have drivers with more than 20 

years of experience, and as a result, they are more likely to engage their drivers in the operation and 

management of their fleets. For example, driver education programs and efficiency incentives are more 

common at private carriers than at their for-hire counterparts. 

The primary motivation for the adoption of TPMS at this fleet was the reduction of emergency roadside 

calls and improved safety of operating their equipment. This is a data-driven organization that decided 

to adopt TPMS for their trailers six years ago due to its lower acquisition cost and anticipated better 

payback relative to ATIS, plus the opportunity to educate and involve drivers in the efforts to properly 

maintain tire pressures. This fleet placed high value on the ability to collect tire inflation history and the 

ability for data to be sent to fleet operations via telematics. TPMS were retrofitted on most existing 

trailers beginning in 2007 and is currently specified on all new trailer purchases.

Recently, in 2011, this fleet has decided to purchase TPMS on all new tractors. The new tractor TPMS 

are supplied by a different manufacturer than the trailer systems, an action that was necessary as a 

common system was not available at the time the decisions were made. The fleet faced a difficult 

decision of whether to purchase tractor systems with the sensors inside or outside the tire. During

preliminary testing, there were some instances of ice and snow accumulation on the sensors mounted 

on the outside of the tire on the valve stem. In contrast, there were concerns of ease of maintenance 

and the difficultly of replacement for sensors mounted inside the tire/wheel assembly. This fleet is 

purchasing a mixture of both systems and will continue to evaluate their performance over time. 

This fleet is pleased with the implementation of these systems on their vehicles. However, they have not 

conducted fuel efficiency testing and did not make specific tire wear data available to NACFE. Results 

from the NACFE payback calculator for this fleet case study are provided in Exhibit 7.2.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 60

Exhibit 7.2 NACFE Tire Pressure Payback Calculator – Private Fleet with TPMS on Tractors and Trailers

Yellow	boxes	are	for	user	inputs

Tractors Trailers Notes:

Number	of	Tractors 	 1,000 Fleet	Input

Number	of	Trailers 	 2,000 Fleet	Input

Miles	per	year 	 100,000 	 50,000 Fleet	Input	&	Calculated

Effectiveness	of	Fleet's	tire	pressure	practices good sub-standard Fleet	Estimate	

Vehicle	average	underinflation 10% 15% Calculated

Cost	of	Tire	Pressure	System $	 750 $	 475 NACFE	Est.	-	See	Source	1.

Installation	Cost	(particularly	if	retrofit)

Total	Installed	Cost $	 750 $	 1,000 Calculated

Equipment	with	TPS 	 800 	 1,600 Fleet	Input

Total	Installed	Cost $	 600,000 $	 760,000 Calculated

Benefits

Roadside	Breakdowns	due	to	low	pressure

Tire	Related	Breakdowns/	Truck	/	Year 1 1 From	NACFE	Fleet	Survey

Avg	cost	/	breakdown	including	tire	cost $	 500 $	 500 From	NACFE	Fleet	Survey

%	Effectiveness	of	TPS	to	detect 70% 70% Fleet	Estimate

Benefit	from	reduced	breakdowns $	 	280,000 $	 5	60,000 Calculated

Tire	Wear

Improvement	in	tire	life 4% 8% Sources	2.	and	3.	below

Tire	cost	per	mile $	 0.021 $	 0.021 Source	5	ATRI	=	$0.042/mile

Improved	cost	per	mile $	 0.001 $	 0.002 Calculated

Benefit	from	tire	wear $	 67,200 $	 1	34,400 Calculated

Fuel	Economy

Improvement	in	Fuel	Efficiency 0.75% 1.25% Sources	2.,	3.	and	4.	below

Fuel	cost	per	mile $	 0.295 $	 0.295 Source	5	ATRI	=	$0.590/mile

Improved	cost	per	mile $	 0.002 $	 0.004 Calculated

Benefit	from	fuel	economy $	 	177,000 $	 2	95,000 Calculated

Total	of	all	Benefits $	 	524,200 $	 9	89,400 Calculated

Payback	in	months 13.74 9.22 Calculated

Sources:

3.	Goodyear	"Radial	Truck	Tire	and	Retread	Service	Manual",	2003,	p.40

4.	Bridgestone	"Real	Answers,	Tires	and	Truck	Fuel	Economy",	2008,	p.25

NACFE	Study	Payback	Calculator:	Tire	Pressure	Systems

2.	Technology	&	Maintenance	Council,	Recommended	Practice	RP	235,	“Guidelines	for	Tire	Inflation	Pressure	Maintenance”,	American	Trucking	

Associations,	Arlington,	VA.,	2012.

1.	An	aggregation	of	NACFE	Study	interviews	-	ATIS	=	$1,000,	TPMS	=	$750	for	intial	tractor	or	trailer	unit	and	an	additional	$475	to	add	an	

attaching	tractor	or	trailer	to	the	first	TPMS.

5.	American	Transportation	Research	Institute,	“An	Analysis	of	the	Operational	Costs	of	Trucking:	A	2012	Update”,	September	2012.	Tire	cost	

per	mile	=	$0.042;	Fuel	cost	per	mile	-	$0.59

©2013	North	American	Council	for	Freight	Efficiency.	All	rights	reserved.

The	contents	of	this	document	are	provided	for	informational	purposes	only	and	do	not	constitute	an	endorsement	of	any	product,	service,	

service	provider,	manufacturer,	or	manufacturing	process.	Nothing	contained	herein	is	intended	to	constitute	legal,	tax,	or	accounting	advice,	

and	NACFE	assumes	no	liability	for	use	of	the	report	contents.	No	portion	of	this	report	or	accompanying	materials	may	be	copied,	reproduced	

or	distributed	in	any	manner	without	express	attribution	to	the	North	American	Council	for	Freight	Efficiency.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 61

8.0 Perspectives for Future Tire Pressure Systems

During the course of the project, tire pressure systems suppliers and fleet users were asked to share 

their perspectives on near- to mid-term developments for products that manage and monitor tire 

inflation in commercial vehicles. This information was combined with results from system testing 

(NHTSA, 2010), and from recent developments in TPMS from the light-duty vehicle segment which has a 

longer history of tire pressure sensor use than heavy-duty vehicles. The discussion is divided into four 

main areas: Functionality, Communications, Operations, and Standardization.

Functionality

The ability to know the actual tire pressure by wheel position and to capitalize on the transmission 

capability of electronic sensors and on-board systems are key advantages of TPMS over most current 

ATIS products. TPMS products are already designed for use on every tire position on the tractor and 

trailer. Conversely, the fact that the vehicle must be stopped to remedy a low tire pressure condition, 

which may have occurred over time due to natural air permeation through the casing or even low 

seepage losses without tire damage, reduces the appeal of TPMS for fleets. Many would prefer to rely 

on ATIS to control pressure within a given range, even if the actual tire pressures are not reported. 

Ideally, it would be preferable to combine the reporting capabilities of TPMS with the automatic 

inflation management functions of ATIS.

In terms of future functionality, industry stakeholders frequently cited the following characteristics as 

most desirable for future systems:

 ATIS Type 1 (vehicle compressed air source) available for drive and steer tires, with some 

type of air routing system through the axle as preferable to air lines attached external to the 

axle. (Note: most stakeholders did not have experience with the ATIS Type 2 systems.)

 Sensor systems combined with ATIS Type 1 or Type 2 to report inflation pressure for each 

individual tire, and to re-inflate tires when no repair or manual intervention is needed.

 ATIS Type 1 or Type 2 with inflate/deflate capability, and which are able to set target 

pressures linked to load, temperature or other operating conditions.

 Ability to block vehicle motion until tires are properly inflated.

The total functionality of the first three bullet points above can already be achieved through a 

disadvantageous practice of purchasing multiple tire pressure systems on each vehicle. This is the most 

expensive and least integrated option. It is anticipated that as tire pressure systems become more 

widespread in the commercial freight industry, product or service offers which take the approach of 

whole vehicle solutions could be more attractive to users than solutions with a comparatively 

fragmented approach, as is more common today. As always, the balance of functionality, price point, 

and system reliability will be crucial for technology adoption. Customers should be able to realize a 

payback for an integrated system within 12-18 months of purchase, without need for further upgrade or 

replacement of components during the subsequent 2-3 years at a minimum.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 62

Communications

Whether through use of tire pressure systems or manual pressure checks, all users want to know the 

inflation condition of their tires in the most straightforward way possible. The communications chain -

from tire measurement to informing driver to maintenance staff to main office to service provider –

plays a critical role in the successful management of tire inflation. 

Different TPMS and ATIS products are distinguished by the type of reporting interface – e.g., in-cab 

display, buttons to press, blinking lights, audible warnings, and so on – which are provided with the 

systems. Users must be able to understand the signals and warnings of the system in order to correctly 

respond to potential underinflation conditions. The design of the user interface(s) has implications for 

the type of education needed by fleet users and potential service providers. 

Some of the concerns and/or needs for future systems which were identified include:

 Operators don’t understand the difference between flashing and steady warning lights. 

Other alerts or information provided by the system may be misunderstood. Notifications 

should be clearer and require less user intervention to get to the root of the problem.

 Capitalize on wireless transmission networks on the vehicle or fleet level to enable other 

functions such as asset tracking, global fleet management, or control of vehicle 

performances such as speed or stability.

 Avoid redundancy of on-board display equipment.

Tire pressure systems need to provide reporting and communications functions that are clear, are 

adaptable for organizations who want to either increase or limit driver responsibility for tire inflation, 

and which have the option to integrate with communications solutions that may already be in use in the 

fleet. On the fleet side, there is a need to prepare the groundwork with training programs for operators, 

maintenance technicians, and service providers to ensure that tire pressure system signals and alerts are 

understood, and that the fleet has established and communicated routine procedures for responding to 

system notifications.

Operations

In general, tire manufacturers recommend pressure checks on a weekly basis, even if tire pressure 

systems are in use. Fleets whose vehicles do not return to a terminal or service location on a daily or 

weekly basis may have to rely on equipment that monitors or manages inflation pressure remotely. On 

the other hand, fleets whose vehicles return to a terminal on a daily basis may have more options for 

choosing tire pressure systems or combinations of methods for tracking tire pressure. Discussions with 

the NACFE team have indicated that, by and large, stakeholders have not reduced their frequency of 

manual pressure checks, but have instead relied on improved pressure maintenance to reduce costs 

associated with vehicle downtime, fuel consumption, and tire wear.

Historically, one of the biggest concerns with sensor-based systems has been the reliability of data 

transmission from the sensors. This can be related to sensor durability, which has seen significant 

improvements in the last decade, or to fleet practices that may compromise sensor performance. 
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 63

Information collected during a yearlong field test (FMCSA, 2009) reported cases of missing sensor data 

due to:

 Sensors which were damaged during tire mounting or demounting.

 Improper installation or re-installation of sensors.

 Technicians unaware that TPMS was installed on vehicle.

 Tires are replaced, but sensors were not remounted.

 Sensors replaced to new wheel position, but system did not recognize the change or was not 

re-programmed to correctly assign the sensor position.

 Lost sensors.

If a fleet plans to use a sensor-based system, particularly across a large number of vehicles,

a sensor management strategy is needed, which includes:

 Procedures to identify vehicles and wheel positions where sensors exist.

 Shop work methods for mounting and changing tires on sensor-equipped vehicles.

 Sensor replacement procedures and processes for sensor inventory management.

This leads into the final section of this chapter, which draws on the experience of sensor-based tire 

pressure systems in light-duty vehicles.

Standardization

Since 2007, all new light-duty vehicles in the United States have been equipped with TPMS, usually 

installed at the vehicle OEM level. In recent years, sensors in these systems have begun to reach the 

end of their normal battery life, requiring replacement of the sensor package. Although new sensors 

can usually be obtained at the OEM dealership service center, the correct sensor may not be available if 

the vehicle owner arranges for tire service to be performed by an independent tire shop. Because TPMS 

is governed by the TREAD Act in the light-duty segment, in certain instances service providers may be 

held liable if a vehicle is released from their shop with a TPMS that is not operating properly.

The maturing of light-duty TPMS technology has had several impacts on the tire pressure sensor 

industry. First, there has been a consolidation in the number of companies supplying sensors to both 

the OEMs and the aftermarket. Second has been the development of “universal” sensors, which are 

designed to operate with components of any TPMS manufacturer. These trends have made it easier for 

vehicle servicers to support the wide range of TPMS products on the market, and to accommodate 

vehicles that may now be equipped with sensors of mixed brands. 

Deployment of systems with individual tire pressure sensors is much less developed in the heavy-duty 

freight transport industry. Generally speaking, commercial vehicle TPMS suppliers have designed and 

patented their sensor technologies; these proprietary sensors can be used with the individual 

manufacturer’s system only, and not across TPMS brands. At some point in the future, although 

probably not in the near term, it is expected that commercial vehicle sensors and systems will be subject 

to the same market pressures seen in light-duty vehicles, and will be driven towards greater component 

standardization.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 64

Regarding ATIS, there is not a similar experience in light-duty vehicles that presently provides insight 

into potential market-driven standardization for this technology.

9.0 Study Conclusions

Given the exhaustive efforts conducted by the study team, the following conclusions are provided.

 The reliability and durability of the available commercial vehicle tire pressure systems is strong. 

As with many new innovations, early issues were identified and corrected and the current 

products are generally believed as acceptable and the companies capable. This project did not 

complete any testing and this conclusion is reached based on previous reporting by FMCSA and 

NHTSA on tire pressure system performance and from anecdotal comments from the fleet and 

tractor and trailer manufacturers.

 Adoption of these solutions is increasing. The systems are moving from retrofit via aftermarket 

to available from the tractor and trailer manufacturers, increasing the quality of the installation 

and decreasing cost with scale.

 Strong options exist for the various truck duty cycles, environmental use and fleet business 

models that deliver the benefits of ensuring proper tire pressure while eliminating or reducing 

the barriers to their use.

 Creative solutions continue to be developed for improved performance, better reliability and 

lower overall costs. 

 The team concludes that the confidence in adopting tire pressure systems should be high given 

a thorough understanding of each fleet’s needs and investigation and testing of systems to meet 

those needs. When completed, a fleet should be confident in selecting the best system for their 

specific needs.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 65

References 

American Trucking Associations, ACT Research Co. LLC, 2013.

AirBAT RF® Tire Pressure Monitoring System, Brochure #571-3078 and #571-3083, STEMCO, 2013. 

American Transportation Research Institute, “An Analysis of the Operational Costs of Trucking: A 2012 

Update”, September 2012.

Benedict, Robert Leon, The Goodyear Tire & Rubber Company, Akron, OH, “Self-Inflating Tire”, U.S. 

Patent Number 8,113,254, February 14, 2012.

Bridgestone Firestone, North American Tire LLC, “Real Answers, Tires& Truck Fuel Economy”, 2008.

CODA Development, 2008, www.selfinflatingtire.com.

Doran Tire Pressure Monitoring System, 360 HD and 360 SL sales brochures, Doran Manufacturing LLC, 

2013.

Doran Tire Pressure Monitoring System, 360 HD and 360 SL User Manual #3673, Revision 1, Doran 

Manufacturing LLC, 2007.

Evans, Larry, John Harris, Ed Terrill, and James D. MacIsaac, Jr, “The Effects of Varying the Levels of 

Nitrogen in the Inflation Gas of Tires on Laboratory Test Performance”, National Highway Traffic Safety 

Administration, Report No. DOT HS 811 094, March 2009.

Federal Motor Carrier Safety Administration, “Commercial Vehicle Tire Condition Sensors”, conducted 

by Booz-Allen-Hamilton, Inc., McLean, VA., November 2003.

Federal Motor Carrier Safety Administration, “Fleet Study of Brake Performance and Tire Pressure 

Sensors”, U.S. Department of Transportation, Report No. FMCSA-PSV-09-001, conducted by Booz- AllenHamilton, Inc., July 2009.

Federal Motor Carrier Safety Administration, “Tire Pressure Monitoring And Maintenance Systems 

Performance Report” U.S. Department of Transportation, Report No. FMCSA-PSV-07-001, conducted by 

Booz- Allen-Hamilton, Inc. and Fisher Fleet Tire Consulting, January, 2007.

Flanigan, Chris, “FMCSA Tire Pressure Monitoring Field Operational Test Results”, presented at 

Technology & Maintenance Council Annual Meeting, Tampa, FL, February, 2011.

Grygier, Paul A., Samuel Daniel, Jr., Richard L. Hoover, and Timothy R. Van Buskirk, “Tire Pressure 

Monitoring System Tests for Medium and Heavy Trucks and Buses”, National Highway Traffic Safety 

Administration, Report No. DOT HS 811 314, Washington, D.C., June, 2010.

Hendrickson, Technical Procedure, TIREMAAX® CP Integrated and PRO Tire Inflation Systems, Subject: 

Installation, Service, and Troubleshooting Procedures, Lit No. T51002, May 2012, Revision B.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 66

Installation and Maintenance Manual 14P, Meritor Tire Inflation Systems (MTIS) by P.S.I.TM, Standard 

MTIS, MTIS with ThermALERTTM System, Revision 06-06.

“MAP-21, Moving Ahead for Progress in the 21st Century”, Public Law 112-141, U.S. Government Printing 

Office, Washington, D.C., July 6, 2012. www.gpo.gov/fdsys/pkg/PLAW-112publ141

Michelin North America, Inc., “Michelin® Truck Tire Service Manual”, May 2011.

National Private Truck Council, ACT Research Co., 2013

North American Council for Freight Efficiency, “2013 Annual Fleet Fuel Efficiency Benchmark Study”, 

March 10, 2013.

On-Highway Equipment Control and Communication Network, “SAE Surface Vehicle Recommended 

Practice J1939/1”, SAE International, November 2012.

Park, Jim, “Nitrogen Tire Inflation”, Heavy Duty Trucking, TruckingInfo.com, August 2010.

Park, Jim, “Preventing Flat Tires”, Heavy Duty Trucking, TruckingInfo.com, April 2013.

Peo, Ralph F., Houde Engineering Corporation, Buffalo, New York, US Patent Number 2,055,983, 

September 29,1936, “Automatic Tire Inflation Attachment”.

PressureGuard® Tire Inflation Systems, Automatic Tire Inflation System Installation Manual, Fleet Air, 

2013.

PressureProTM Tire Pressure Monitoring System, on-line parts catalog, Advantage Pressure Pro LLC, 2013.

Renier, Grant J., Cycloid Company, Pittsburgh, Pennsylvania, US Patent Number 5,409,049, April 25, 

1993, “Tangential Tire Pressurizing and Regulating Apparatus”.

Renier, Grant J., Cycloid Company, Pittsburgh, PA., “Tire Pressuring and Regulating Apparatus”, U.S. 

Patent Number 5,201,968, April 13, 1993.

Richardson, Brandon, Palo Alto, CA, “Tire Inflation System”, U.S. Patent Application Publication US 

2012/0186714, July 26,2012.

Olney, Ross D., Hughes Aircraft Company, Los Angeles, California, US Patent Number 5,355,924, October 

18, 1994, “Vehicle Wheel Including Self-Inflating Mechanism”.

“Safe, Accountable, Flexible, and Efficient Transportation Equity Act: A Legacy for Users”, Public Law 

109-59, U.S. Government Printing Office, Washington, D.C., August, 10, 2005. 

www.gpo.gov/fdsys/pkg/PLAW-109publ59
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 67

SmarTireTM Tire Pressure Monitoring System, Brochure #BW2755, Bendix Commercial Vehicle Systems 

LLC, 2010.

SmarTireTM TPMS Pressure and Temperature Chart, #BW2824, Bendix Commercial Vehicle Systems LLC, 

2010.

STEMCO AerisTM Installation and Service Manual, Part Number: 01-571-8300, Revision: 12/4/2012, Rev. 

B.

“TEA-21 Transportation Equity Act for the 21st Century”, Public Law 105-178, U.S. Government Printing 

Office, Stock No. 869-036-00025-1, Washington, D.C., June 9, 1998. www.fhwa.dot.gov/tea21

Technology & Maintenance Council, Recommended Practice RP 235, “Guidelines for Tire Inflation 

Pressure Maintenance”, American Trucking Associations, Arlington, VA., 2012.

The Goodyear Tire & Rubber Company, “Radial Truck Tire and Retread Service Manual”, 2003.

“Tire Pressure Monitoring Systems – For Medium and Heavy Duty Highway Vehicles”, SAE Surface 

Vehicle Recommended Practice J2848-1, SAE International, April 2010.

“Tire Pressure Systems – Maintenance (ATIS) Type for Medium and Heavy Duty Highway Vehicles”, SAE 

Surface Vehicle Recommended Practice J2848-2, SAE International, June 2011.

TIreVigilTM TPMS, Product description brochure, TireStamp, Inc., Rochester Hills, MI., 2013.

“TREAD Act, Transportation Recall, Enhancement, Accountability, and Documentation”, Public Law 106-

414, U.S. Government Printing Office, Washington, D.C., November 1, 2000. 

www.gpo.gov/fdsys/pkg/PLAW-106publ414

U.S. Environmental Protection Agency, SmartWay, 2000 Traverwood Drive, Ann Arbor, MI., 2013. 

www.epa.gov/smartway/partnership

Valor Tire Pressure Monitoring System, sales brochure, Valor, 2013.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 68

Appendix A: Product Summary Sheets for Selected Tire Pressure Technology Categories

Product summary sheets were developed for seven TPMS and five ATIS products and are included in 

Appendix A of this report. The appearance, or lack thereof, of an individual commercial product in this

Appendix is not an indication of its performance, quality, functionality, or of any endorsement or 

recommendation by NACFE. NACFE does not endorse products or manufacturers. Individual products in 

each category can exhibit equivalent performance. An expanded list of tire pressure systems by 

category, including primary attributes and company contact information, is included in Appendix B. 

Products are listed in alphabetical order by the product commercial name. Product and product 

features may not be all-inclusive.

PRODUCT CATEGORY: Tire Pressure Monitoring Systems (TPMS)

Sub-Category: Wheel-End Sensors with Transmission Capability
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Product Name ContiPressureCheckTM

Company Name Continental Automotive Systems, Inc.

Product Website www.conti-online.com

System Type Tire Pressure Monitoring

Pressure Sensor Type Tire patch / Internal tire mounted

Measurement Type Pressure and Temperature

Application Steer, Drive, and Trailer

Sensor Mounted Position Tire patch / Internal tire mounted

Inside Tire Y

Sensor Visible on Wheel End N

Sensor Removal Necessary to Fill Tire N

Transmitting Antenna Y

Number of Receiving Antennas 1

Measurement Type Pressure and Temperature

Temperature Compensation of Reported Pressure Y

Number of Low Pressure Alert Settings 2

Low Pressure Alert 1 Factory Setting 10% below Target Pressure

Low Pressure Alert 2 Factory Setting 18% below Target Pressure

Fast Leak Alert N

High Pressure Alert Factory set at 24% above Target Pressure

High Temperature Alert Level 239oF

User Programmable Pressure Alert Level Y

In Cab Display Y

Procurement Options OEM and Retrofit

Maximum Number of Wheel Positions 24

Tractor/Truck Fitment Y

Trailer Fitment Y

Hardware Installation Time for Tractor/Truck 3 hours - Retrofit (including installation of

sensors in tires)

Hardware Installation Time for Trailer

2 hours - Retrofit (including installation of

sensors in tires)

Drop and Hook Feature N

Standard Warranty

2 years parts only; OEM would be

contractual

- Location of sensor enables reporting of internal air and tire temperature independent of effects of other wheelend components.

- Possible to have trailer only system with indicator lamp mounted on trailer to alert driver.

- Continues to operate 24/7, unless deactivated (if preferred for parked trailer, for example)

Product Information

System Summary

The ContiPressureCheck system utilizes sensors mounted inside the

summit area of the tire to provide accurate temperature and 

pressure readings. The sensor, inside a rubber container, is glued 

onto the tire. The tire pressure and temperature are sent wirelessly

to an ECU antenna mounted on the tractor, which then transmits the

data to the in-cab display. Alerts and warnings are displayed inside

the cab. The system can be used for tractors, trailers or in

combination.

Product Detail

Specific Features

- Only current TPMS product with sensor mounted internal to tire in summit area.

Space intentional y left blank.

Images not available.
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Product Name Pressure Pro

TM

Company Name Advantage Pressure Pro, LLC

Product Website www.advantagepressurepro.com

System Type Tire Pressure Monitoring

Pressure Sensor Type

Sensor mounted externally to hub with tire

hoses connecting to valve stems

Measurement Type Pressure and Temperature

Application Steer, Drive, and Trailer

Images used with permission of Advantage Pressure Pro,

LLC

Sensor Mounted Position External valve stem

Inside Tire N

Sensor Visible on Wheel End Y

Sensor Removal Necessary to Fill Tire Y

Transmitting Antenna Integral to sensor

Number of Receiving Antennas 1

Measurement Type Pressure and Temperature

Temperature Compensation of Reported Pressure N

Number of Low Pressure Alert Settings 2

Low Pressure Alert 1 Factory Setting 12.5% below Target Pressure

Low Pressure Alert 2 Factory Setting 25% below Target Pressure

Fast Leak Alert N

High Pressure Alert

User adjustable from 10%-45% above

Target Pressure

High Temperature Alert Level 194oF

User Programmable Pressure Alert Level Y

In Cab Display Y

Procurement Options Retrofit

Maximum Number of Wheel Positions

34 with base system option; 64 with Drop 

& Hook system option

Tractor/Truck Fitment Y

Trailer Fitment Y

Hardware Installation Time for Tractor/Truck 30 min

Hardware Installation Time for Trailer 20 min

Drop and Hook Feature

Y (only with Intelligent Monitor and 

Repeater options)

Standard Warranty 1 year limited

- Sensor uses as its target or baseline pressure the tire pressure at the time of sensor installation.

- Continues to operate 24/7, monitors every 7 seconds

- Sensors are available to be used with other systems

Product Information

System Summary

The sensor mounted on each valve stem, monitors tire air pressure

and temperature, then wirelessly transmits the signal to the

intelligent repeater (trailer) or the in-cab display. The repeater will

wirelessly relay the data collected from the trailer tires to the tractor.

The in-cab display monitors tire pressure of each tire position every 7

seconds.

Product Detail

Specific Features

- Offers a wide range of products from base sensor+monitor (+ antenna option) package to sensor+Intelligent 

Monitor+Repeater+J1939 Gateway

- RS232 capability for data logging and transmission and CANBUS option for communications to third party

telematics service provider.
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Appendix A: Product Summary Sheets for Selected Tire Pressure Technology Categories

PRODUCT CATEGORY: Automatic Tire Inflation Systems (ATIS)

Sub-Category: ATIS Type 1 – Vehicle Tank Air Source
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Product Name Meritor Tire Inflation Systems by P.S.I.TM

Company Name Pressure Systems International, Inc

Product Website www.psi-atis.com

System Type Automatic Tire Inflation

Measurement Type Pressure

Application Trailer

Images used with permission of Pressure Systems International,

Inc.

Air source Trailer air tank

Pressurized axle (Y/N) Y

Pressure range of operation 85-150 psi

Option for User to reset Target Pressure Y

Driver Alert of system operation Y

Driver Alert of fast leak Y

Fast Leak Alert Level Any air flow to the tire

Difference below Target Pressure that will trigger system operation Always Pressurized

Difference below Target Pressure that will illuminate trailer lamp Any air flow to the tire

Cutoff pressure to isolate ATIS from air tank 85 psi

Inflation rate capability 7 ft3/min

Number of Axles/Tire Positions Monitored Regulator supports up to 5 axles on a trailer*

Inflate only or Inflate/Relief functionality Inflate only

Manually check pressure without disconnect (Y/N) N

Operates when parked (Y/N) N

Supplier recommended system inspection cycle(s)

- Tire inspection at regular intervals;

- System wheel end component inspection

recommended at every tire removal;

- System inspection recommended every 100,000

miles or 12 months for standard commercial vehicle

operations.

Procurement Options Trailer OEM and Retrofit

Tractor/Truck Fitment N

Trailer Fitment Y

Hardware Installation Time for Trailer 4 hours

Standard Warranty 3 years or 500,000 miles

* Axle capacity depends on vehicle compressor, braking system requirements.

- Axle venting via tee vent and hubcap vents avert wheel end pressure buildup.

- Flow switch in controller monitors air flow to activate trailer lamp.

- Self-draining filter screens contaminants.

System Summary

Meritor® Tire Inflation Systems connects all of the tires on a trailer

to a controlled air supply to fill and maintain air pressure level. The

existing trailer air supply flows to a control box and then to each axle. The

axles carry air through a rotary union assembly at the spindle end and 

distributes to each tire as needed. If a tire is leaking at a level which

cannot be compensated by the system, check valves in delivery lines 

prevent loss of pressure in the remaining tires. The indicator light on the

front of the trailer will come ON to signal excessive air loss caused by a

leaking tire or a loose connection, or both.

Product Detail

Specific Features

 - ThermALERT

TM option to warn when the wheel end is operating at high temperatures.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 79

Product Name PressureGuard

TM

Company Name Fleet Air, LLC

Product Website www.fleet-air.com

System Type Automatic Tire Inflation

Measurement Type Pressure

Application Trailer

Images used with permission of fleet Air, LLC

Air source Trailer air tank

Pressurized axle (Y/N) N

Pressure range of operation 85-125 psi

Option for User to reset Target Pressure Y

Driver Alert of system operation Y

Driver Alert of fast leak Y

Fast Leak Alert Level +/- 20 psi

Difference below Target Pressure that will trigger system operation Always Pressurized

Difference below Target Pressure that will illluminate trailer lamp 20 psi below Target Pressure*

Cutoff pressure to isolate ATIS from air tank 70 psi

Inflation rate capability 5 - 10 psi/min**

Number of Axles/Tire Positions Monitored

Regulator supports up to 8 axles on a

trailer***

Inflate only or Inflate/Relief functionality Inflate / Relief

Manually check pressure without tire hose disconnect (Y/N) N

Operates when parked (Y/N) N

Supplier recommended system inspection cycle(s) Verify actual tire pressures periodically

Procurement Options Trailer OEM and Retrofit

Tractor/Truck Fitment N

Trailer Fitment Y

Hardware Installation Time for Trailer 4 hours

Standard Warranty

3 years or 500,000 miles (rotating shafts,

bushings, and seals)

* Option to adjust warning pressure level to 10 psi below Target Pressure.

** Depending on the air delivered to the system from the tractor’s compressor via the trailer’s air supply.

*** Axle capacity depends on vehicle compressor, braking system requirements.

- Patented rotary union enclosed and protected by a patented aluminum hub cap

- Pressure sensor in control unit detects pressure loss instead of flow switch.

Product Information

System Summary

The PressureGuard

TM System routes air from the trailer’s air brake tank

through the axle, by way of tubing, to the hubcaps and then to the tires.

The system is designed to maintain tire pressure at a factory preset level. If

a loss of air pressure occurs, the pressure protection valve will shut off the

system to prevent air loss from the air brake tank. A trailer warning light is 

used to alert the driver of an air leak.

Product Detail

Specific Features

- Internal trailer axle air lines do not pressurize trailer axle tube.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 80

Product Name TIREMAAX

® PRO

Company Name Hendrickson

Product Website www.hendrickson-intl.com

System Type Automatic Tire Inflation

Measurement Type Pressure

Application Trailer

Images used with permission of Hendrickson

Air source Trailer air tank

Pressurized axle (Y/N) N

Pressure range of operation 80-120 psi dual; 90-120 psi single

Option for User to reset Target Pressure Y

Driver Alert of system operation Y

Driver Alert of fast leak N

Fast Leak Alert Level not applicable

Difference below Target Pressure that will trigger system operation 1 - 2 psi

Difference below Target Pressure that will illuminate trailer lamp

Will illuminate when there is a flow of air to the

tire

Cutoff pressure to isolate ATIS from air tank 70 psi +/- 5 psi

Inflation rate capability 10 psi per 2 min (one tire)

Number of Axles/Tire Positions Monitored Regulator supports up to 3 axles on a trailer*

Inflate only or Inflate/Relief functionality Inflate / Relief

Manually check pressure without disconnect (Y/N) N

Operates when parked (Y/N) N

Supplier recommended system inspection cycle(s)

- Manually check tire pressures per tire

manufacturers' recommendations for inspection

intervals;

- Check indicator lamp and tire hoses on quarterly 

cycle;

- System connections and controller operation

annually.

Procurement Options Trailer OEM and Retrofit

Tractor/Truck Fitment N

Trailer Fitment Y

Hardware Installation Time for Trailer 8 hours

Standard Warranty

- 3 years parts and labor for "external" components - 

controller, hoses, plumbing;

- 5 years parts and labor - hubcaps, rotary seal, axle

hose;

- 7-years parts and labor when coupled with

Hendrickson HXL7® extended service wheel end

- Retrofit kit: 3 years parts, 1 year labor

* Additional axle capacity depends on vehicle compressor, braking system requirements.

- Flow switch in controller monitors air flow to activate trailer lamp.

- Air relief function back through controller prevents tire overinflation.

- Pressure can be equalized across all tires with pressure relief function.

Product Information

System Summary

TIREMAAX

® PRO uses the trailer supply tank to provide a constant air source

to the controller. The TIREMAAX

® PRO controller continuously monitors the

air pressure in the tires and adjusts the tire pressure as necessary to

maintain the proper target pressure. The controller is connected to the tires 

through internal supply lines inside the trailer axle. These axle lines connect 

to a rotary union and tire hoses that allow the air to flow to the rotating 

tires. The system provides a pressure relief function to reduce air pressure in

tires reaching an overpressure threshold level.

Product Detail

Specific Features

- Internal trailer axle air lines do not pressurize trailer axle tube.

Ventless	

Hub	Cap	

Patented	

Axle	

Filter	

Nonpressurized	

Axle	

Integrated	

Hubcap	

Design	

Hendrickson	

Axle	Vent	
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 81

Appendix A: Product Summary Sheets for Selected Tire Pressure Technology Categories

PRODUCT CATEGORY: Automatic Tire Inflation Systems (ATIS)

Sub-Category: ATIS Type 2A – Direct Atmospheric Air Source with Self-Contained Pump
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 82

Product Name HaloTM Tire Inflator

Company Name Aperia Technologies, Inc.

Product Website www.aperiatech.com

System Type Automatic Tire Inflation

Measurement Type Pressure

Application Steer, Drive, and Trailer

Images used with permission of Aperia Technologies, Inc.

Air source Atmospheric air (air surrounding the vehicle)

Pressurized axle (Y/N) N

Pressure range of operation 30 - 140 psi

Option for User to reset Target Pressure N

Driver Alert of system operation N

Driver Alert of fast leak N

Fast Leak Alert Level not applicable

Difference below Target Pressure that will trigger system operation Always Pressurized

Difference below Target Pressure that will illuminate trailer lamp not applicable

Cutoff pressure to isolate ATIS from air tank not applicable

Inflation rate capability 6 psi/hour per tire

Number of Axles/Tire Positions Monitored 1 Halo unit per wheel end

Inflate only or Inflate/Relief functionality Inflate only

Manually check pressure without disconnect (Y/N) Y

Operates when parked (Y/N) N

Supplier recommended system inspection cycle(s)

Inspect tire hoses, unit mounting, and clean

intake filter at each tire change, at least once

per year.

Procurement Options Retrofit

Tractor/Truck Fitment Y (drive)

Trailer Fitment Y

Hardware Installation Time for Trailer 5-10 minutes per wheel end

Standard Warranty 3-year limited

- Current product can be used on both drive and trailer applications; does not rely on air line connections through or along the

axles to a vehicle air source.

- Bolt-on to a variety of hub types for quick installation.

Product Information

System Summary

When the vehicle is moving, outside air is drawn into a central hub-mounted 

device and is compressed, building up pressure. The unit provides air flow

as long as air pressure inside the tire is below the pre-set target inflation

pressure of the device. Air flow shuts off automatically when the desired air

pressure level is reached.

Product Detail

Specific Features

- Self-contained pump unit uses the wheel rotational motion to maintain optimal tire pressure.
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 83

Appendix B: Expanded List of Tire Pressure Systems Suppliers

CATEGORY:

Sub-Category:

Product	Name Company	Name

Interviewed	

by	NACFE

Address Phone Website Email	Contact Sensor	Type

AirBAT	RF® Stemco *

300	Industrial	Blvd

Longview,	TX	75602

800.527.8492 www.batrf.com

Chris	Steph

chris.steph@stemco.com

External	wheel-mounted

ContiPressureCheckTM Continental	AG *

Continental	Tire	the	Americas,	LLC

1830	MacMillan	Park	Drive

Fort	Mill,	SC	29707

704.583.8665

www.contionline.com/www/transport_de_enDJ	Frye

DJ.Frye@conti-na.com

Internal	tire	mounted

Doran	360HDTM	and	

Doran	360	SmartLinkTM

Doran	Manufacturing,	

LLC

*

2851	Massachusetts	Avenue

Cincinnati,	OH	45224

866.816.7233 www.doranmfg.com

Jim	Samocki

samocki_jim@doranmfg.com

External	valve	stem	mounted

IVTMTM	Integrated	

Vehicle	Tire	Pressure	

Monitoring

WABCO

2770	Research	Drive

Rochester	Hills,	MI	48309

248.270.9253 www.wabco-auto.com

Stephen	Hampson

stephen.hampson@wabcoauto.comExternal	wheel-mounted

PressureProTM

Advantage	Pressure	Pro,	

LLC

*

205	West	Wall	Street

Harrisonville,	MO	64701

800.959.3505 www.advantagepressurepro.com

Phil	Zaroor

pzaroor@pressurepro.us

External	valve	stem	mounted

SmarTireTM

Bendix	Commercial	

Vehicle	Systems	LLC

*

901	Cleveland	Street

Elyria,	OH	44035

800.247.2725 www.bendix.com

Jon	Intagliata

jon.intagliata@bendix.com

Internal	wheel-mounted

TireMinder® Minder	Research	Inc.

3000	SE	Waaler	Street

Stuart,	FL	34997

772.463.6522 www.minderresearch.com info@MinderResearch.com External	valve	stem	mounted

Tire	Sentry® Fleet	Specialities	Co.

31328	Via	Colinas

Westlake	Village,	CA	91362

800.350.3556 www.tiresentry.com info@tiresentry.com External	valve	stem	mounted

TireVigilTM	TPMS	and

TIreVigilTM	TPMS	Trailer

TireStamp	Inc. *

3508	Wedgewood	Drive,	Suite	101

Rochester	Hills,	MI	48306

248.373.0312 www.tirestamp.com

Peggy	Fisher

peggy.fisher@tirestamp.com

Internal	valve	stem	mounted	

or

External	valve	stem	mounted

TST	TPMS

Truck	Systems	

Technologies	Inc.

4250	Keith	Bridge	Road,	Suite	200

Cumming,	GA	30041

770.889.9102 www.tsttruck.com dcovington@tsttruck.com External	valve	stem	mounted

Valor	TPMS Valor	TPMS *

4320	Harvester	Road

Burlington,	Ontario

L7L	5S4	Canada

800.568.9188 www.valortpms.com

Michael	Kutzscher

m.kutzscher@valortpms.com

Internal	wheel-mounted

or

Internal	valve	stem	mounted

Sub-Category:

Product	Name Company	Name

Interviewed	

by	NACFE

Address Phone Website Email	Contact Sensor	Type

PNEUSCAN	ATM	Tire	

Pressure	Check

VENTECH	USA	LP

2105	Barrett	Park	Drive,	#109

Kennesaw,	Georgia	30144

770.352.9300 www.ventechusa.com sales@ventechusa.com

Drive-over	sensor	plates	-	floor	

mounted

Tire	ScanTM	System Tekscan,	Inc.

307	West	First	Street

South	Boston,	MA	02127

800.248.3669 www.tekscan.com/industrial/

tirescan-system.html

n/a

Drive-over	sensor	plates	-	floor	

mounted,	in-ground	mounted,	

or	test	equipment	mounted

Tire	Pressure	Monitoring	Systems	(TPMS)

Wheel-End	Sensors	with	Transmission	Capability

Pressure	Sensing	Mats
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 84

Appendix B: Expanded List of Tire Pressure Systems Suppliers

CATEGORY:

Sub-Category:

Product	Name Company	Name

Interviewed	

by	NACFE

Address Phone Website Email	Contact Sensor	Type

Cat's	Eye®

Link®	Manufacturing,	

Ltd. *

223	15th	Street	NE

Sioux	Center,	IA	51250

800.222.6283 www.linkmfg.com n/a

External	wheel	mounted	

sensor	is	connected	to	valve	

stems	via	tire	hoses

CrossfireTM Dual	Dynamics

2241	Humphrey	Avenue

Lincoln,	NE	68521

800.228.0394 www.dualdynamics.com info@dualdynamics.com

External	wheel	mounted	

sensor	is	connected	to	valve	

stems	via	tire	hoses

Dual	Tire	Pressure	Equalizers

Dual	Tire	Pressure	Equalizers
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 85

Appendix B: Expanded List of Tire Pressure Systems Suppliers

CATEGORY:

Sub-Category:

Product	Name Company	Name

Interviewed	

by	NACFE

Address Phone Website Email	Contact Air	source	type

AerisTM Stemco *

300	Industrial	Blvd

Longview,	TX	75602

800.527.8492 www.stemcoaeris.com

Chris	Steph

chris.steph@stemco.com

Trailer	air	tank

AIRGO®	Automatic	Tire	

Inflation	System

AIRGO®	Systems

Parkland	Trailer	Inc.

21-1201	Grassmere	Road

West	St.	Paul,	Manitoba

R4A	1C4	Canada

866.694.9679 www.airgo.ca info@airgo.ca Trailer	air	tank

Meritor®	Tire	Inflation	

System	by	P.S.I.TM

P.S.I.TM	Pressure	Systems	

International *

3023	Interstate	Drive

San	Antonio,	TX	78210

210.222.1926 www.psi-atis.com

Frank	Sonzala

Frank.Sonzala@psi-atis.com

Trailer	air	tank

PressureGuardTM	Tire	

Inflation	Systems

Fleet	Air *

1921	Columbus	Road

Cleveland,	OH	44113

216.689.9900 www.fleet-air.com

Jeff	Therber

jeff@fleet-air.com

Trailer	air	tank

TIREMAAX®	PRO	and	

TIREMAAX®	CP

Hendrickson *

4770	Navarre	Road	SW

Canton,	OH	44706

866.743.3247 www.hendrickson-intl.com

Matt	Wilson

mwilson@hendrickson-intl.com

Trailer	air	tank

T-RAC Trans	Technologies	Co

15	Bowen	Court,	Suite	B

Cartersville,	GA	30120

800.527.7729 www.transtechcom.com info@transtechcom.com Trailer	air	tank

VIGIATM	Tire	Inflation	

Systems

RCR	Systems	Ltd

1500	Avenue	Road

P.O.	Box	1352

Toronto,	Ontario

M5M	0A1	Canada

416.512.7275 www.vigia.ca info@vigia.ca Truck	and/or	Trailer	air	tank

Sub-Category:

Product	Name Company	Name

Interviewed	

by	NACFE

Address Phone Website Email	Contact Air	source	type

Goodyear	Air	

Maintenance	

Technology	(AMT)

Goodyear	Tire	&	Rubber	

Company *

200	Innovation	Way

Akron,	OH	44316

330.796.2121 www.goodyear.com

Brian	Buckham

brian_buckham@goodyear.com

Atmospheric	air	source

Halo	Tire	Inflator Aperia	Technologies	Inc. *

160	S.	Linden	Ave,	Suite	130

South	San	Francisco,	CA	94080

415.494.9624 www.aperiatech.com

Joshua	Carter

josh@aperiatech.com

Atmospheric	air	source

Automatic	Tire	Inflation	Systems	(ATIS)

ATIS	Type	1	-	Truck	or	Trailer	Tank	Air	Source

ATIS	Type	2	-	Atmospheric	Air	Source	(external	to	vehicle)
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 86

Appendix B: Expanded List of Tire Pressure Systems Suppliers

CATEGORY:

Product	Name Company	Name

Interviewed	

by	NACFE

Address Phone Website Email	Contact Air	source	type

Spicer®	Central	Tire	

Inflation	System

Dana	Commercial	

Vehicle	Products	Group

3939	Technology	Drive

Maumee,	OH	43537

419.887.3000 www.dana.com n/a Truck	air	tank

TIREBOSSTM	Tire	

Pressure	Control

Tire	Pressure	Control	

International	Ltd.

15803	121A	Avenue

Edmonton,	Alberta

T5V	1B1	Canada

888.338.3587 www.tirepressurecontrol.com info@tireboss.com Truck	and/or	Trailer	air	tank

Central	Tire	Inflation	Systems	(ATIS)
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 87

Appendix B: Expanded List of Tire Pressure Systems Suppliers

CATEGORY:

Sub-Category:

Product	Name Company	Name

Interviewed	

by	NACFE

Address Phone Website

NitroFillTM	nitrogen	

generators

NitroFillTM

3750	Park	Central	Blvd.	N

Pompano	Beach,	FL	33064

877.246.3455 www.nitrofill.com

Nitrogen	Inflation	

Towers	(various	models)

Branick	Industries

4245	Main	Ave.

Fargo,	NC	58103

800.437.4394 www.branick.com

TireSaverTM	Tire	Inflation	

Systems

Parker	Hannifin	Corp

242	Neck	Road

Haverhill,	MA	01835-0723

800.343.4048 www.parker.com

Sub-Category:

Product	Name Company	Name

Interviewed	

by	NACFE

Address Phone Website Email	Contact

DuraSeal	Technology®

Goodyear	Tire	&	Rubber	

Company *

200	Innovation	Way

Akron,	OH	44316

330.796.2121 www.goodyear.com/truck/

technology

Brian	Buckham

brian_buckham@goodyear.com

Sub-Category:

Product	Name Company	Name

Interviewed	

by	NACFE

Address Phone Website

EcoSeal®

International	Marketing	

Inc.

25	Penncraft	Ave,	Suite	C

P.O.	Box	2002

Chambersburg,	PA	17201

800.233.7086 www.imiproducts.com

Ride-OnTM	CHSTM Inovex	Industries	Inc.

45681	Oakbrook	Court

Unit	102

Sterling,	VA	20166

888.374.3366 www.ride-on.com

#743	SchaefferSealTM	

Tire	Sealant

Schaeffer	

Manufacturing	Co.

102	Barton	St

St.	Louis,	MO	63104

800.325.9962 www.schaefferoil.com

Tire	Lyna® Lyna	Manufacturing	Inc.

1125	West	15th	Street

North	Vancouver

British	Columbia,	Canada	V7P	1M7

888.619.6669 www.tirelyna.com

UltrasealTM	Tire	Sealant Gempler's®

P.O.	Box	44993

Madison,	WI	53744-4993

800.382.8473 www.gemplers.com

Aftermarket	Sealants

Passive	Pressure	Containment	Approaches

Nitrogen	Inflation	

Tires	with	Built-In	Sealant	Layer
 Tire Pressure Systems – Confidence Report 

Aug-13 NACFE Page 88

Appendix C: Contributing Systems Suppliers

NACFE would like to acknowledge the contributions of the following suppliers of tire pressure 

systems for their assistance to the study team through interviews, valuable insights, product 

documentation and information support for the Tire Pressure Systems project. 

Advantage Pressure Pro, LLC

Aperia Technologies

Bendix Commercial Vehicle Systems, LLC

Continental AG

Doran Manufacturing, LLC

Fleet Air

Hendrickson

International Marketing Inc.

Link Manufacturing, Ltd.

P.S.I. Pressure Systems International

Stemco

The Goodyear Tire & Rubber Company

TireStamp Inc.

Valor TPMS