Regulations Requiring Onboard Diagnostic 

Systems on 2010 and Later Heavy-Duty 

Engines Used in Highway Vehicles Over 

14,000 Pounds; Revisions to Onboard 

Diagnostic Requirements for Diesel 

Highway Vehicles Under 14,000 Pounds 

Final Technical Support Document 
Regulations Requiring Onboard Diagnostic 

Systems on 2010 and Later Heavy-Duty 

Engines Used in Highway Vehicles Over 

14,000 Pounds; Revisions to Onboard 

Diagnostic Requirements for Diesel 

Highway Vehicles Under 14,000 Pounds 

Final Technical Support Document 

Assessment and Standards Division 

Office of Transportation and Air Quality 

U.S. Environmental Protection Agency 

EPA-420-R-08-019 

December 2008 
Final Technical Support Document; HDOBD Final Rule 

Table of Contents 

1. Introduction 1 

2. Technological Feasibility 1 

2.1 Update on ZrO2 NOx Sensor Development 1 

2.1.1 Current Technology 1 

2.1.2 Future Improvements 4 

2.1.3 Heavy-duty NOx Detection for 2010 Technology Engines 5 

2.2 Diesel Particulate Filter Monitoring 5 

2.2.1 Alternative to a PM Threshold for DPF Monitor 5 

2.2.2 Monitoring Area for Alternative Approach 6 

2.2.3 Engine Data Supporting Alternative DPF Monitor Approach 7 

3. Costs 10 

3.1 Cost Analysis for Engines Used in Over 14,000 Pound Applications 11 

3.1.1 Variable Costs 11 

3.1.2 Fixed Costs 14 

3.1.3 Total Costs 34 

3.2 Cost Analysis for 8,500 to 14,000 Pound Diesel Applications 35 

3.3 Updated 2007/2010 HD Highway Costs Including OBD 41 

References 45 

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Final Technical Support Document; HDOBD Final Rule 

List of Tables 

Table 1. Data from 5.9L Diesel Engine with DPF Modified to Simulate a Failed Part 9 

Table 2. Estimated OBD Hardware Costs for Diesel and Gasoline Engines Used in Vehicles Over 

Table 3. Total OBD Variable Costs for Diesel and Gasoline Engines Used in Vehicles Over 14,000 

Table 4. R&D Costs for OBD Algorithm Development and Application – Diesel Engines for Over 

Table 5. R&D Costs for OBD Algorithm Development and Application – Gasoline Engines for Over 

Table 8. OBD R&D Test Cell Demand per Manufacturer – Diesel Engines for Over 14,000 Pound 

Table 9. OBD R&D Test Cell Demand per Manufacturer – Gasoline Engines for Over 14,000 Pound 

Table 10. Summary of OBD R&D Costs – Diesel and Gasoline Engines for Over 14,000 Pound 

Table 11. Cost for OBD Certification Demonstration Limit Parts – Diesel Engines for Over 14,000 

Table 12. OBD Certification and Production Evaluation Testing Costs – Diesel Engines for Over 

Table 13. OBD Certification and Production Evaluation Testing Costs – Gasoline Engines for Over 

Table 14. Total OBD Fixed Costs – Diesel and Gasoline Engines for Over 14,000 Pound 

Table 15. Total Estimated OBD Costs – Diesel and Gasoline Engines for Over 14,000 Pound 

Table 19. OBD Certification and Production Evaluation Testing Costs – Diesel Applications Under 

14,000 Pounds 12 

Pounds 14 

14,000 Pound Applications 16 

14,000 Pound Applications 19 

Table 6. OBD R&D Test Cell Costs – Diesel Engines for Over 14,000 Pound Applications 21 

Table 7. OBD R&D Test Cell Costs – Gasoline Engines for Over 14,000 Pound Applications 22 

Applications 23 

Applications 23 

Applications 24 

Pound Applications 26 

14,000 Pound Applications 28 

14,000 Pound Applications 29 

Applications 33 

Applications 34 

Table 16. Total Estimated OBD Costs per Engine for Over 14,000 Pound Applications 35 

Table 17. R&D Costs for OBD Algorithm Development and Application – 37 

Table 18. OBD R&D Test Cell Costs – Diesel Applications Under 14,000 Pounds 38 

14,000 Pounds 40 

Table 20. Total Estimated OBD Costs – Diesel Applications Under 14,000 Pounds 41 

Table 21. Costs of the 2007/2010 Heavy-duty Highway Program 42 

Table 22. Updated 2007/2010 Program Costs Including New OBD-Related Costs 43 

Table 23. Consumer Price Index Data 44

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Final Technical Support Document; HDOBD Final Rule 

1. Introduction 

This document contains technical details in support of the final requirements for onboard 

diagnostic (OBD) systems on highway applications over 14,000 pounds. The details of these 

requirements are not covered in this document and can be found in the preamble to the final 

regulations contained in the docket for the rule.1 

The details presented in this document support statements in the technological feasibility 

and costs sections of the preamble for this rule. As such, this document is broken into two 

sections: technological feasibility and costs. Note that many of our technological feasibility 

arguments are presented in the preamble and the Summary and Analysis of Comments 

document which are also contained in the docket for this rule. The preamble to the rule 

contains only a brief summary of our cost estimates while the details behind our cost 

estimates are presented here. 

2. Technological Feasibility 

2.1 Update on ZrO2 NOx Sensor Development 

2.1.1 Current Technology 

a. Manufacturers 

Zirconium Oxide NOx sensors have been developed to measure modal NOx emissions 

from lean burn engines. Currently there are three companies that are selling these devices. 

They are as follows: NGK Automotive Ceramics, Ionotec, and Ceramatec. 

b. Measurement Principle 

Typical NOx sensor design consists of two internal cavities and three oxygen pumping 

cells designed to measure both oxygen (air to fuel ratio measurement) and NOx 

concentrations. The most common commercial sensor used today is based on zirconia (ZrO2) 

partly or fully stabilized with ytteria (Y2O3). The presence of oxygen vacancies in the 

material makes the mobility of the oxygen ion O2

- possible. The resulting conductivity is 

very low at room temperatures, but reaches values of a wet electrolyte when the sensor is 

heated up to < 600°C. An oxygen sensor can be constructed if the solid electrolyte is 

provided with porous electrodes separating two gas chambers. At higher cell temperatures 

the solid electrolyte conducts oxygen ions, thus an oxygen concentration difference between 

the two chambers results in a voltage signal. The half cell reactions are as follows: 

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Final Technical Support Document; HDOBD Final Rule 

4e- + O2(test) Æ 2O2

2­

2O2

2- Æ 4e- + O2(ref)

 This voltage signal is described in a very good agreement by the Nernst equation: 

⎞

⎟

⎟

PO2( ref ) RT ⎛ ⎛

⎜

⎝

⎞

⎟

⎠

sample gas. 

⎜

⎜

Where R is the ideal gas constant, T is absolute temperature, F is the Faraday constant, 

PO2(ref) is the partial pressure of the reference gas and PO2(test) is the partial pressure of the 

In general, the measurement concept consists of: 

1) Lowering the oxygen concentration of a measuring gas to a predetermined level in the 

first internal cavity, in which NOx does not decompose, and

2) Further lowering the oxygen concentration of the measuring gas to a predetermined 

level in the second internal cavity, in which NOx decomposes on a measuring 

electrode and the oxygen generated is detected as a sensor signal. 

Figure 3 shows a cross-sectional view of the NOx sensor element. Each part in the

The first internal cavity connects a measuring gas stream through the first diffusion path 

under a predetermined diffusion resistance. There is an oxygen pumping cell and an oxygen 

sensing cell inside the first internal cavity. 

The first oxygen pumping cell consists of a pair of first pumping (+) and (-) electrodes 

sensing element functions as follows: 

First Internal Cavity 

E = ln

4F PO ⎝ 2(test ) ⎠

Figure 3. Cross-sectional view of NOx sensing element.2 

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Final Technical Support Document; HDOBD Final Rule 

on the ZrO2-1 layer, in order to lower the oxygen concentration to a predetermined level. 

The first pumping electrode (+) is platinum and the (-) electrode is a platinum/gold alloy to 

reduce NOx reduction catalytic activity. 

The oxygen sensing cell consists of the first pumping (-) electrode in the first internal 

cavity and a reference electrode in an air duct. This allows monitoring of the oxygen 

concentration in the first internal cavity by generated electromotive force and feedback to the 

first oxygen pumping cell. 

Second Internal Cavity 

The second internal cavity connects to the first internal cavity through the second 

diffusion path under a predetermined diffusion resistance. There are two different oxygen 

pumping cells and an oxygen sensing cell inside the second internal cavity. 

The second oxygen pumping cell consists of the second pumping (-) electrode in the 

second internal cavity and the first pumping (+) electrode on the ZrO2-1 layer, in order to 

further lower the oxygen concentration to a predetermined level. The second pumping (-) 

electrode is also made of a platinum/gold alloy. 

The oxygen sensing cell consists of the second pumping (-) electrode and the reference 

electrode in the air duct to monitor the oxygen concentration in the second internal cavity by 

generated electromotive force and feedback to the second oxygen pumping cell. 

The NOx sensing cell consists of a measuring electrode in the second internal cavity and 

the reference electrode in the air duct. The measuring electrode is rhodium and has a NOx 

reduction catalytic activity. Therefore, NOx decomposes on the measuring electrode and the 

oxygen generated is detected as an oxygen pumping current in the NOx sensing cell. The 

sensor signal is in proportion to the NOx concentration in the measuring gas.2 

c. Measurement Range 

ZrO2 NOx sensors are currently available in the 0 – 500 ppm, 0 – 1500 ppm, and 0 – 

2000 ppm range. Reported accuracy is in the ± 10% range for readings in the 100 to 2000 

ppm range and ± 10 ppm for readings in the 0 to 100 ppm range. 

d. Interference 

ZrO2 NOx sensor interference has been limited to ammonia (NH3). Sensitivity to NH3 

has been shown to be up to 65% of the amount of NH3 present in the sample gas. This NH3 

is converted to NOx in the internal cavities of the sensor and then measured.3 This 

phenomenon may only plague urea SCR applications, where over dosing of urea could lead 

to NH3 slip. In addition, urea SCR feedback control studies have shown that the NH3 

interference signal is discernable from the NOx signal and can, in effect, allow the design of a 

better feedback control loop than a NOx sensor that doesn’t have any NH3 cross-sensitivity. 

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Final Technical Support Document; HDOBD Final Rule 

The signal conditioning method developed, resulted in a linear output for both NH3 and NOx 

from the NOx sensor downstream of the catalyst.3 

e. Durability 

Durability data for diesel applications is limited. NGK has reported data for 1000 hours 

of testing (60,000 mile equivalent) on a 2.5 L diesel engine. This data showed that the aged 

sensor achieved ± 20 ppm (or ± 7% measurement error) NOx accuracy for a 300 ppm NOx 

sample on a 0 to 2000 ppm range sensor. This is almost equivalent to the accuracy of the 

fresh sensor in this concentration range.4 

Twenty-five NGK NOx sensors in the 0 to 2000 ppm range have undergone 6,000 hours 

of aging on a 12 L Caterpillar C-12 engine. Five of these sensors are in the engine out 

location, 10 are located downstream of the DPF and upstream of the SCR catalyst, and 10 are 

located downstream of the clean-up catalyst. NOx sensors are compared every 1,000 hours 

and are independently calibrated every 2,000 hours. 

Typical sensor NOx exposure varies by location. On average, the 15 sensors located 

upstream of the SCR catalyst were exposed to NOx concentrations in the 100 to 600 ppm 

range. This is close to the expected range of engine out exhaust emissions for a 2010 engine, 

but the range maximum is on the low side. The 10 sensors located downstream of the 

cleanup catalyst were exposed to NOx concentrations in the 10 to 200 ppm range. For testing 

out to 2,000 hours, of the pre-catalyst sensors, 12 degraded by 3 to 4%, while the remaining 

three degraded by 5 to 7%. Of the post NOx catalyst sensors, all 10 had minimal degradation. 

For those sensors that degraded a similar amount, degradation was linear. 

For testing out to 4,000 hours, of the pre-catalyst sensors, 11 degraded by 4 to 6%, while 

the remaining four degraded by 7 to 8%. Of the post NOx catalyst sensors, 9 had minimal 

degradation while one degraded 7%. For those sensors that degraded a similar amount, 

degradation was linear. Overall relative error ranged from 8% at engine-out concentrations 

to minimal degradation at lower concentrations.5 

For testing out to 6,000 hours, of the pre-catalyst sensors, 5 degraded by 5 to 6%, while 

the remaining ten degraded by 7 to 12%. Of the post NOx catalyst sensors, 8 had minimal 

degradation while two degraded 10%. For those sensors that degraded a similar amount, 

degradation was linear. Overall relative error ranged from 10% at engine-out concentrations 

to minimal degradation at lower concentrations.6 

2.1.2 Future Improvements 

As with any maturing technologies, it is expected that improvements will be made to 

sensor accuracy and durability in the near future. Requests by engine manufacturers have 

been made to instrument manufacturers to develop sensors that have improved accuracy in 

the 0 to 100 ppm range. Instrument manufacturers are complying with these requests and it 

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Final Technical Support Document; HDOBD Final Rule 

is expected that NOx sensors in the 0 to 100 ppm range with a zero hour ± 5 ppm accuracy 

and aged ± 10 ppm accuracy will be available by the middle of 2010. 

2.1.3 Heavy-duty NOx Detection for 2010 Technology Engines 

a. Future NOx Emission Levels 

It is expected that NOx concentrations downstream of an emission control system on an 

engine meeting the 2010 NOx standard will be in the 0 to 50 ppm range, on average, 

depending on engine speed, load, and the state of the emission control system (ECS). 

As an example, a 5.9 L Cummins ISB meeting the 2010 NOx standard for the FTP (0.13 

g/hp-hr) and SET (0.12 g/hp-hr) using a NOx adsorber based ECS will have average NOx 

emissions ranging from 0 to 60 ppm.

7

 Data from the APBF-DEC Heavy-Duty NOx 

Adsorber/DPF Project: Heavy Duty Linehaul Platform reported NOx emissions downstream 

of the ECS in the range of 0 to 200 ppm for an engine emitting NOx in the range of 0.05 to 

0.5 g/hp-hr NOx over 2000 hours.8 It is important to note that the average NOx emissions are 

less than 40 ppm for this engine and ECS. Therefore it is important to note that NOx spikes 

larger than the average will have to be dealt with accordingly by the OBD system. 

b. Current NOx Sensor Detection Limits 

Current NOx sensors have a stated accuracy of ± 10 ppm in the zero to 100 ppm range 

for a 0 to 2000 ppm range. Accuracies for some sensors have been reported as high as ± 30 

ppm. With this in mind, current NOx sensor technology should be able detect NOx emissions 

that exceed the standard by 2 to 3 times the 2010 limit. 

c. Future NOx Sensor Detection Limits 

If NOx sensor manufacturers are able to develop the proposed 0 to 100 ppm range sensor 

with ± 5 ppm accuracy, it should be possible to accurately measure emissions increases as 

low as 1.5 times the 2010 NOx emission standard. With sensor development underway, this 

sensor should be available by early to mid 2006 for evaluation. 

2.2 Diesel Particulate Filter Monitoring 

2.2.1 Alternative to a PM Threshold for DPF Monitor 

Given that sensors which can directly measure exhaust PM will not be available for 

commercial sale in 2010, an alternative to a PM threshold monitor is provided. This 

alternative is a differential pressure (or delta pressure) sensor-based approach which can be 

used to determine the inherent functionality of the DPF. When the engine is operated under 

moderate-to-high speed and load conditions, the exhaust flowing through a DPF creates a 

pressure drop across the device. This pressure drop is measured by a differential pressure 

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Final Technical Support Document; HDOBD Final Rule 

(dP) sensor, and is influenced by exhaust gas conditions (mass flow rate and temperature), 

the level of soot loading on the filter, and the structural integrity of the filter (e.g. cracks 

and/or substrate damage which would allow exhaust gasses to bypass the filter media). By 

comparing the dP observed whenever the engine is operated in the monitored region to the 

expected dP for a nominal, clean filter under similar operating conditions, a judgment can be 

made as to whether the DPF is performing properly (i.e. exhaust gas is flowing through the 

filter media, not bypassing it). If a dP value is observed which is lower than the expected dP 

value minus some detectable change in the dP signal, it is likely that some failure of the DPF 

has occurred and PM emissions have increased. The “detectable change in dP” that must be 

detected is determined by running the engine at a single mode on the Supplemental 

Emissions Test (SET), recording the dP value with a clean DPF, and multiplying this dP 

value by 0.5; the result of this calculation becomes the detectable change in dP value. For a 

given operating point within the monitored region, the observed dP is continuously compared 

to the result of the “expected dP” minus the “detectable change in dP”; if the observed dP 

drops below the result of this calculation for more than 5 seconds, a malfunction is present 

and a DTC would be stored. 

2.2.2 Monitoring Area for Alternative Approach 

At lower engine speed and load conditions (which result in lower exhaust mass flow, and 

hence, a lower dP across the DPF), the observed dP is low (less than 4 kPa in our testing on a 

5.9L engine, see Table 1), and if the sensitivity of a dP sensor is +/- 1kPa, the system is 

unable to reliably distinguish between good DPF and a damaged DPF with lower flow 

restriction. Since the dP sensor-based monitor would not be reliable under conditions where 

that exhaust mass flow is low, the monitored area will defined using SET modes where 

significant engine air flow conditions exist and a meaningful dP signal is available. We 

believe that DPF failures can be accurately and reliably identified using this approach. 

Figure 4 illustrates an example of the engine speed and load operating conditions under 

which this alternative DPF monitor will function and how the enable conditions for the 

monitor are defined using SET modes A100, A75, B50, and C50. 

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Final Technical Support Document; HDOBD Final Rule 

0 

100 

200 

300 

400 

500 

600 

700 

800 

900 

1000 

Torque (N-m) 

Monitored Area 

800 1000 1200 1400 1600 1800 2000 2200 2400 2600 2800 

Engine Speed (RPM) 

Torque SET modes DPF Monitoring Area 

Figure 4. Example of Engine Speed-Load Area Where Alternative DPF Monitor Is 

Active 

2.2.3 Engine Data Supporting Alternative DPF Monitor Approach 

A Cummins 5.9L ISB engine was used to determine the affect that a simulated DPF 

failure would have on the dP sensor output. The DPF used for this test was a 200 cell persquare-inch, wall-flow design, 9 inches in diameter and 11 inches in length. To simulate a 

“failed” part (e.g.. one in which a portion of the rear face and volume is missing due to 

excessive temperature excursions during an un-controlled regeneration event), a 5 inch hole 

was machined in the rear face of the filter to a depth of 5.5 inches (50% of the filter length). 

In addition, the channel plugs on half of the remaining rear face were machined off to 

increase the percentage of channels that were “open.” In total, 18% of the filter volume was 

removed and 33% of the filter face area had open channels. The photo in Figure 5 shows the 

rear face of the modified DPF. 

The baseline case was run using a clean and completely intact DPF (i.e., the part before 

modification to simulate a “failed” part) and the engine was operated at the SET modes, 

where engine and exhaust data were recorded. The modified or “failed” DPF was then 

installed, run under the same test conditions, and the results are summarized in Table 1. 

Using the “B50” mode of the SET on the baseline test, a “detectable change in dP” value of 

1.7 kPa was established (i.e. dP @ B50 = 3.38 kPa; 3.38*0.5 = 1.7). Subtracting this 1.7 kPa 

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Final Technical Support Document; HDOBD Final Rule 

detectable dP change from the dP observed at each mode in the baseline test, an observed dP 

value at which a malfunction can be detected is established. As the test data show, for the 

particular DPF failure that was simulated, a malfunction could be detected if the engine were 

operated at or above the “B75” engine speed and load conditions. At test conditions where 

the malfunction would have been detected (i.e. B75, B100, C75, and C100), the post-DPF 

PM levels were 1.8-to-3.1 times the 0.01 g/bhp•hr PM emission standard (i.e., below our 

threshold of the PM standard + 0.04). For DPF failures which result in a larger change in the 

dP signal (e.g. more of the DPF volume is missing and/or more channels are open), the 

engine speeds and loads at which a malfunction can be detected become lower as well. 

Figure 5. Rear Face of DPF Modified to Simulate Missing Substrate Due to Melting 

During Un-Controlled Regeneration 

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Final Technical Support Document; HDOBD Final Rule 

Table 1. Data from 5.9L Diesel Engine with DPF Modified to Simulate a Failed Part 

SET Mode Engine Speed 

(RPM) 

Torque 

(N•m) 

Mass exh flow 

(kg/hr) 

EGT 

(°C) 

PM - DPF-In 

(g/bhp•hr) 

PM - DPF-Out 

(g/bhp•hr) 

DPF dP 

(kPa) 

Calculated 

Change in dP 

(base - mod) 

Fault Detected ? 

(change in dP > 

dP@B50 * 0.5) 

A75 - baseline 1619 675 551.09 453 n/a 0.002 3.91 1.5 No A75 - modified 555.07 450 n/a 0.011 2.46 

A100 - baseline 1619 877 677.36 484 n/a 0.005 5.41 1.5 No A100 - modified 685.11 481 n/a 0.021 3.95 

B50 - baseline 1947 445 552.07 375 0.047 0.001 3.38 1.2 No B50 - modified 555.96 375 0.047 0.028 2.14 

B75 - baseline 1947 668 721.67 427 0.032 0.002 5.29 2.0 Yes B75 - modified 723.36 421 0.032 0.018 3.25 

B100 - baseline 1947 876 862.25 457 0.039 0.001 6.78 2.5 Yes B100 - modified 864.30 460 0.039 0.022 4.28 

C50 - baseline 2275 407 673.30 n/a n/a n/a 4.21 1.6 No C50 - modified 675.87 353 n/a 0.021 2.60 

C75 - baseline 2275 610 862.27 414 0.077 0.002 6.17 2.0 Yes C75 - modified 868.35 n/a 0.077 n/a 4.13 

C100 - baseline 2275 811 991.89 476 0.044 0.001 8.09 2.6 Yes C100 - modified 992.28 477 0.044 0.031 5.53 

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Final Technical Support Document; HDOBD Final Rule 

3. Costs 

This section provides the details behind the cost analysis done in support of our 

over14,000 pound OBD program and our changes to the existing under14,000 pound heavyduty diesel OBD requirements. Details associated with the new requirements and changes to 

existing requirements can be found in the preamble to the rulemaking and are not presented 

here. As a result, there may be details within this report that can be understood only by 

reading the associated preamble for the rulemaking. 

The final cost analysis differs from the draft cost analysis (i.e., the analysis done in 

support of the proposed rule) in three ways. First, we have included costs for aging limit 

parts to their OBD thresholds. We inadvertently did not include those costs in the draft 

analysis. Discussion of this can be found in the Summary and Analysis of Comments 

document in Section VI.B. These newly added costs are presented in Section 3.1.2.b of this 

document. Second, while in the proposal we estimated lower warranty costs beginning in 

2013, we have delayed that until 2016 in the final rule. This is discussed in Section VI.A of 

the Summary and Analysis of Comments document and in Section 3.1.1 of this document. 

Third, we have adjusted all costs to 2007 dollars – the draft analysis used 2004 dollars – by 

using the Consumer Price Index. As a result, all costs presented here are slightly higher than 

in the draft analysis although we have not changed the analysis with the exception of this 

adjustment for inflation and, as mentioned previously, the addition of costs for aging of limit 

parts and delay of lower warranty costs. 

This analysis breaks estimated costs into two primary categories: variable costs and fixed 

costs. Variable costs are those costs associated with any new hardware required to meet the 

requirements, the associated assembly time to install that hardware, and any increased 

warranty costs associated with the new hardware. Variable costs are additionally marked up 

to account for both manufacturer and dealer overhead and carrying costs. The 

manufacturer’s carrying cost was estimated to be four percent of the direct costs to account 

for the capital cost of the extra inventory and the incremental costs of insurance, handling, 

and storage. The dealer’s carrying cost was estimated to be three percent of their direct costs 

to account for the cost of capital tied up in inventory. We adopted this same approach to 

markups in the heavy-duty 2007/2010 rule and our more recent Nonroad Tier 4 rule based on 

industry input.9 

Fixed costs considered here are those for research and development (R&D), certification, 

and production evaluation testing. The fixed costs for engine R&D are estimated to be 

incurred over the four-year period preceding introduction of the engine. The fixed costs for 

certification include costs associated with demonstration testing of OBD parent engines 

including the “limit” parts used to demonstrate detection of malfunctions at or near the 

applicable OBD thresholds. The demonstration testing costs are estimated to be incurred one 

year preceding introduction of the engine while the production evaluation testing is estimated 

to occur in the same year as introduction. Importantly, none of the fixed costs estimated here 

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Final Technical Support Document; HDOBD Final Rule 

consider the recent California Air Resources Board approved requirements for over 14,000 

pound OBD.10 

We present all of these costs in the year during which we estimate they will be incurred 

by manufacturers over the 30 year time period following publication of the final rule. We 

then calculate a 30 year net present value of those cost streams using both a three percent and 

a seven percent discount rate to reflect the time value of money at both ends of the most 

likely range. 

We present all costs in 2007 dollars. We refer to both near term costs and long term costs. 

The near term costs represent those costs when warranty costs are estimated to be the highest. 

The long term costs consider the effects of a reduction in warranty costs. For warranty costs, 

we have estimated a three percent near term rate for warranty claims and a one percent long 

term rate for warranty claims. 

3.1 Cost Analysis for Engines Used in Over 14,000 Pound Applications 

3.1.1 Variable Costs 

The variable costs we have estimated represent those costs associated with various 

sensors that we believe would have to be added to the engine to provide the required OBD 

monitoring capability. Our variable (i.e., hardware) cost estimates are summarized in Table 

2. 

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Final Technical Support Document; HDOBD Final Rule 

Table 2. Estimated OBD Hardware Costs for Diesel and Gasoline Engines Used in Vehicles Over 14,000 

Pounds 

(2007 dollars) 

Diesel Gasoline 

2010-2012 Model Year 

New Hardware 

ECU upgrade $ 33 $ 11 

Purge solenoid for evap leak check $ - $ 11 

Pressure sensor for evap leak check $ - $ 11 

Subtotal $ 33 $ 33 

Assembly labor (hours) 0.10 0.30 

Assembly labor cost $ 3 $ 10 

Assembly labor overhead at 40% $ 1 $ 4 

Cost to Mfr $ 38 $ 47 

Warranty cost - near term at 3% claim rate $ 4 $ 4 

Mfr. Carrying cost at 4% $ 2 $ 2 

Cost to Buyer -- 2010-2012 $ 43 $ 53 

2013+ Model Year 

New Hardware 

MIL and wiring $ 11 $ 11 

Subtotal (2010+2013) $ 44 $ 44 

Assembly labor (hours) 0.20 0.40 

Assembly labor cost $ 7 $ 13 

Assembly labor overhead at 40% $ 3 $ 5 

Cost to Mfr $ 53 $ 62 

Warranty cost - long term at 3% claim rate $ 5 $ 5 

Mfr carrying cost at 4% $ 2 $ 2 

Cost to Buyer -- 2013-2015 $ 60 $ 70 

2016+ Model Year 

Cost to Mfr $ 53 $ 62 

Warranty cost - long term at 1% claim rate $ 2 $ 2 

Mfr carrying cost at 4% $ 2 $ 2 

Cost to Buyer -- long term $ 57 $ 66 

For the 2010 model year, we believe that both diesel and gasoline engines would have to 

upgrade their engine control computers, or engine control units, to accommodate the 

increased computing capacity required for the proposed OBD. We have estimated this cost 

at $33 per engine for diesel engines and $11 for gasoline engines, inclusive of supplier 

markup. We have estimated a different cost because we believe that the gasoline engines are 

using computers similar, if not in fact identical to, their under 14,000 pound counterparts. 

Therefore, those computer upgrades should cost little, if anything. For diesel engines, we 

believe that the OBD requirements will result in a more substantial upgrade to existing 

computers. Also for the 2010 model year, we believe that gasoline engines would have to 

add both a purge solenoid and a pressure sensor for the evaporative system monitoring 

requirement. We have estimated the cost of both of these items at $11 a piece inclusive of 

supplier markup. We believe that the other sensors needed by the OBD system on both 

diesel and gasoline engines will already be on the engines for either emissions control and/or 

protection of the engine (e.g., temperature sensors used to protect against condensation 

formation caused by overcooling of the EGR gases—engine protection—can also be used to 

monitor the effectiveness of the EGR cooler—OBD). The result is a manufacturer cost 

subtotal of $33 for both diesel and gasoline engines in the 2010 model year. Note that we 

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Final Technical Support Document; HDOBD Final Rule 

have not included costs for a malfunction indicator light (MIL) and associated wiring in the 

2010 timeframe since we are not requiring a dedicated MIL until the 2013 model year. 

We have estimated that adding these sensors and actuators will require increased 

assembly time. We have estimated these times at one-tenth of an hour for diesel engines and 

one-third of an hour for gasoline engines (i.e., six minutes for each newly added part). We 

have estimated a labor rate of $33 per hour for this assembly along with overhead at 40 

percent. This results in an estimated cost to the manufacturer of $38 and $47 for diesel and 

gasoline engines, respectively, in the 2010 model year. 

We have included a warranty cost recovery estimating a three percent warranty claim rate 

in the near term. We have also included a four percent manufacturer carrying cost to cover 

increased insurance and inventory costs incurred by the manufacturer.11 Including these 

costs results in an end cost to the buyer of roughly $43 and $53 for diesel and gasoline 

engines, respectively, in the 2010 model year. 

For the 2013 model year, we have included costs associated with the dedicated MIL and 

its wiring. These costs were estimated at $11 per engine inclusive of supplier markup. 

Following the same process for assembly costs (another one-tenth of an hour per engine), 

warranty costs (three percent claim rate since many engines will be complying with the rule 

beginning in 2013), and carrying costs, we have estimated the 2013 model year hardware 

cost to the buyer at roughly $60 and $70 for diesel and gasoline engines, respectively. 

For the 2016 model year, we have reduced the costs associated with warranty by 

estimating a one percent claim rate since all engines will have complied with the rule for 

several years. Including the carrying costs, we have estimated the 2016 and later, or longterm, hardware cost to the buyer at $57 and $66 for diesel and gasoline engines, respectively. 

To determine the fleetwide estimated hardware costs, or total variable costs, we looked at 

the projected over 14,000 pound sales data from our 2004 model year certification database 

which showed projected US sales less projected California sales of 614,500 for diesel 

engines and 39,400 for gasoline engines. In the 2010 through 2012 model years, we 

estimated 50 percent of engines would comply with the proposed OBD requirements based 

on our proposed phase-in schedule. For model years 2013 and later, we will have 100 

percent compliance. Applying the estimated hardware costs presented in Table 2 to the 

appropriate projected sales in each model year through 2035, estimating a two percent 

growth in sales based on 2004 sales, results in a 30 year net present value (NPV) cost of $620 

million and $47 million for diesel and gasoline engines, respectively, using a three percent 

discount rate. These costs, including a NPV at a seven percent rate, are shown in Table 3. 

13 
$0 0% $0 $0 0% $0 $0

$0 0% $0 $0 0% $0 $0

$0 0% $0 $0 0% $0 $0

$0 0% $0 $0 0% $0 $0

Final Technical Support Document; HDOBD Final Rule 

Table 3. Total OBD Variable Costs for Diesel and Gasoline Engines Used in Vehicles Over 14,000 

Pounds 

(2007 dollars) 

Year CY 

Diesel Gasoline Total Hardware 

Projected Sales $/engine % complying Subtotal Projected Sales $/engine % complying Subtotal Costs 

1 2006 639,103 40,976 

2 2007 651,393 41,764 

3 2008 663,684 42,552 

4 2009 675,974 43,340 

5 2010 688,265 $43 50% $14,852,000 44,128 $53 50% $1,164,000 $16,016,000 

6 2011 700,555 $43 50% $15,117,000 44,916 $53 50% $1,185,000 $16,302,000 

7 2012 712,846 $43 50% $15,382,000 45,704 $53 50% $1,205,000 $16,587,000 

8 2013 725,136 $60 100% $43,646,000 46,492 $70 100% $3,244,000 $46,890,000 

9 2014 737,426 $60 100% $44,385,000 47,280 $70 100% $3,299,000 $47,684,000 

10 2015 749,717 $60 100% $45,125,000 48,068 $70 100% $3,354,000 $48,479,000 

11 2016 762,007 $57 100% $43,356,000 48,856 $66 100% $3,248,000 $46,604,000 

12 2017 774,298 $57 100% $44,055,000 49,644 $66 100% $3,301,000 $47,356,000 

13 2018 786,588 $57 100% $44,754,000 50,432 $66 100% $3,353,000 $48,107,000 

14 2019 798,879 $57 100% $45,454,000 51,220 $66 100% $3,405,000 $48,859,000 

15 2020 811,169 $57 100% $46,153,000 52,008 $66 100% $3,458,000 $49,611,000 

16 2021 823,459 $57 100% $46,852,000 52,796 $66 100% $3,510,000 $50,362,000 

17 2022 835,750 $57 100% $47,551,000 53,584 $66 100% $3,563,000 $51,114,000 

18 2023 848,040 $57 100% $48,251,000 54,372 $66 100% $3,615,000 $51,866,000 

19 2024 860,331 $57 100% $48,950,000 55,160 $66 100% $3,667,000 $52,617,000 

20 2025 872,621 $57 100% $49,649,000 55,948 $66 100% $3,720,000 $53,369,000 

21 2026 884,912 $57 100% $50,349,000 56,736 $66 100% $3,772,000 $54,121,000 

22 2027 897,202 $57 100% $51,048,000 57,524 $66 100% $3,825,000 $54,873,000 

23 2028 909,493 $57 100% $51,747,000 58,312 $66 100% $3,877,000 $55,624,000 

24 2029 921,783 $57 100% $52,446,000 59,100 $66 100% $3,929,000 $56,375,000 

25 2030 934,073 $57 100% $53,146,000 59,888 $66 100% $3,982,000 $57,128,000 

26 2031 946,364 $57 100% $53,845,000 60,676 $66 100% $4,034,000 $57,879,000 

27 2032 958,654 $57 100% $54,544,000 61,464 $66 100% $4,086,000 $58,630,000 

28 2033 970,945 $57 100% $55,244,000 62,252 $66 100% $4,139,000 $59,383,000 

29 2034 983,235 $57 100% $55,943,000 63,040 $66 100% $4,191,000 $60,134,000 

30 2035 995,526 $57 100% $56,642,000 63,828 $66 100% $4,244,000 $60,886,000 

NPV @ 3% $685,964,000 $51,463,000 $737,427,000 

NPV @ 7% $363,769,000 $27,315,000 $391,084,000 

3.1.2 Fixed Costs 

We have estimated fixed costs for research and development (R&D), certification, and 

production evaluation testing. The R&D costs include the costs to develop the computer 

algorithms required to diagnose engine and emission control systems, and the costs for 

applying the developed algorithms to each engine family and to each variant within each 

engine family. The certification costs include the costs associated with testing of durability 

data vehicles (i.e., the OBD parent engines), the costs associated with generating the “limit” 

parts that are required to demonstrate OBD detection at or near the applicable emissions 

thresholds, and the costs associated with generating the necessary certification 

documentation. Production evaluation testing costs consist of the costs associated with the 

three different elements of production evaluation testing. 

a. Research & Development Costs 

We have broken the estimated R&D costs into three separate categories. The first of 

these is the cost for developing computer controlled diagnostic algorithms. These costs are 

estimated to be incurred once per manufacturer since once an algorithm is developed, it can, 

practically speaking, be used over and over again with only minor changes, if any, to 

improve upon the original. The second R&D cost is that for applying the manufacturer’s 

developed algorithm to each of its engine families. Each engine family may have a different 

14 
Final Technical Support Document; HDOBD Final Rule 

number of cylinders or different emissions control architecture (e.g., different combinations 

of aftertreatment devices) and the algorithm may have to be adapted for each of these engine 

families. Consequently, this cost is estimated to be incurred once for each of the engine 

families expected to be sold. The third R&D cost is that for applying the algorithm that has 

been adapted for each engine family to every variant within each engine family. Variants 

within engine families have different horsepower and/or torque characteristics and, therefore, 

the adapted algorithm would have to be fine tuned to each of the engine family’s variants. 

These costs are estimated to be incurred once for each of the remaining variants within each 

family (i.e., one variant will use the adapted algorithm while the remaining variants will 

require further fine tuning). 

We have estimated separate development and separate application costs for the different 

types of monitors—system monitors, rationality monitors, and comprehensive component 

monitors. System monitors are generally the most difficult monitors and for the most part are 

those monitors for which an emissions threshold exists. Nonetheless, most system monitors 

are not correlated to an emissions threshold and are, instead, functional monitors that can 

detect a malfunctioning component prior to emissions exceeding the applicable thresholds. 

For such monitors, manufacturers generally forego the more costly emissions correlation 

work and rely on the functional check alone which saves both time and money. 

We have estimated that an engineer and a technician would be involved in most of the 

development work since much of the work will entail testing on an engine test bed. We have 

estimated that an engineer costs $110,000 a year while a technician costs $66,000 a year, and 

that they each work 48 forty hour weeks per year. Table 4 shows these R&D costs for diesel 

engines. The total costs shown represent industry totals for ten manufacturers. 

15 
Final Technical Support Document; HDOBD Final Rule 

Table 4. R&D Costs for OBD Algorithm Development and Application – Diesel Engines for Over 14,000 

Pound Applications 

(2007 dollars) 

Fixed Costs - Diesel 

A. Algorithm Development Costs weeks/monitor Cost/monitor # of monitors Total/Mfr Total

 System Threshold Monitors 

Engineer $ 

Technician $ 

Subtotal 

System Functional Monitors 

Engineer $ 

Technician $ 

Subtotal 

30 

15 

20 

5 

$69,000 

$21,000 

$90,000 

$46,000 

$7,000 

$53,000 

9 

41 

$810,000 

$2,173,000 

$8,100,000 

$21,730,000 

CCM Rationality Monitors 

Engineer $ 

Technician $ 

Subtotal 

CCM Continuity Monitors 

Engineer $ 

Technician $ 

Subtotal 

15 

1 

2 

0 

$34,000 

$1,000 

$35,000 

$5,000 

$0 

$5,000 

50 

80 

$1,750,000 

$400,000 

$17,500,000 

$4,000,000 

Total $5,133,000 $51,330,000 

B. Application Costs to each Family weeks/monitor Cost/monitor # of monitors Total/Family # families/mfr Total/Mfr Total

 System Threshold Monitors 

Engineer $ 

Technician $ 

Subtotal 

System Functional Monitors 

Engineer $ 

Technician $ 

Subtotal 

5 

10 

5 

10 

$11,000 

$14,000 

$25,000 

$11,000 

$14,000 

$25,000 

9 

41 

$225,000 

$1,025,000 

6.5 

6.5 

$1,463,000 

$6,663,000 

$14,630,000 

$66,630,000 

CCM Rationality Monitors 

Engineer $ 

Technician $ 

Subtotal 

Total 

3 

1 

$7,000 

$1,000 

$8,000 50 $400,000 

$1,650,000 

6.5 $2,600,000 

$10,726,000 

$26,000,000 

$107,260,000 

C. Application Costs to remaining Variants Total/Variant # variants/family # families/mfr Total/Mfr Total 

Total $413,000 4 6.5 $10,738,000 $107,380,000 

For diesel engines, using industry input and our own engineering analysis, we have 

estimated that there will be roughly 50 system monitors. Of these, we treated 9 as threshold 

monitors with the remainders being functional monitors.a Based on industry input, we have 

also estimated that there will be an additional 50 rationality monitors and 80 circuit 

continuity monitors. 

a

 The 9 threshold monitors for diesel engines, based on our engineering judgment, would be: fuel system 

pressure high; fuel system injection timing too advanced; fuel system injection timing too retarded; EGR low 

flow; EGR slow response; EGR low cooling; variable valve timing (VVT) above target; VVT below target; 

VVT slow response; NOx catalyst system conversion; NOx catalyst system reductant delivery; NOx adsorber 

performance; DPF filtering performance; NOx sensor slow response; and, NOx sensor offset. We have 

estimated that 50 percent of engines would do threshold monitoring for fuel systems (based on changes in the 

final rule to the electronic unit injector provisions). Similarly, we have estimated 50 percent of engines to be 

SCR equipped with 50 percent being NOx adsorber equipped. We have also estimated 50 percent to be EGR 

equipped with 50 percent being VVT equipped. Using these factors on the list of threshold monitors results in 9 

monitors for the “average” diesel engine. 

16 
Final Technical Support Document; HDOBD Final Rule 

We believe that algorithm development will be more resource intensive than will 

algorithm application (on a per monitor basis). For algorithm development of system 

threshold monitors, we have estimated 30 engineer-weeks of development per monitor and 

15 technician-weeks per monitor while for system functional monitors we have estimated 20 

and 5 weeks of development per monitor, respectively. For rationality monitors, we have 

estimated 15 engineer-weeks and only one technician-week since determining the proper 

rationality—the engineer’s job—can be difficult but testing and verifying that it works—the 

technician’s job—should not be difficult. For circuit continuity monitors, we have estimated 

only two engineer-weeks and no technician weeks since these monitors are relatively straight 

forward (open circuit/short circuit). 

Multiplying by the engineer and technician labor rates and the number of monitors results 

in total costs of $51 million which will be incurred during the four year period leading up to 

implementation (i.e., during the years 2006 through 2009). These costs are shown in Table 

4A. 

For algorithm application to each engine family, we have estimated that the majority of 

the work will entail testing and, therefore, it will be done by the technician. For system 

threshold monitors and functional monitors, we have estimated five engineer-weeks and 10 

technician weeks. For rationality monitors, we have estimated three engineer-weeks and one 

technician-week because adapting these algorithms should be more straight forward than 

adapting system monitors. For circuit continuity monitors, we have estimated no costs for 

applying algorithms since these should be directly applicable to any engine. 

These algorithm application costs will be incurred on each engine family. Our 2004 

model year database shows a total of 65 diesel engine families meant for over 14,000 pound 

vehicles. The database also shows 10 heavy-duty diesel engine manufacturers for an average 

of 6.5 engine families per manufacturer. Multiplying the estimated weeks by the appropriate 

engineering and technician labor rates, the number of monitors, the number of engine 

families per manufacturer, and the number of manufacturers results in total costs of $107 

million dollars. These costs are shown in Table 4B. These costs will be incurred on some 

engine families during the four years leading up to the 2010 model year (i.e., one engine 

family per manufacturer) and on the remaining families during the four years leading up to 

the 2013 model year. 

To estimate the costs for fine tuning the adapted algorithm to the remaining variants 

within each engine family, we have considered this to take roughly one-quarter the effort 

required for the initial engine family application. Therefore, the $413,000 cost per variant is 

estimated as one-quarter of the $1.65 million per family cost to apply the algorithm to the 

engine family. The variant based application costs are estimated to be incurred by those 

remaining variants within the engine family (i.e., these costs are not incurred on the variant 

for which the initial application work was done). Based on input from industry, we have 

estimated that there is an average of five variants per engine family. As a result, the variant 

application cost will be incurred on four variants per engine family. Multiplying the cost per 

variant by the number of remaining variants, the average number of engine families per 

manufacturer and again by the number of manufacturers results in another $107 million 

17 
Final Technical Support Document; HDOBD Final Rule 

dollars in total costs. These costs are shown in Table 4C. These costs will be incurred on 

some engine families during the four years leading up to the 2010 model year (i.e., four 

variants within one engine family per manufacturer) and on the variants of the remaining 

families during the four years leading up to the 2013 model year. 

We have used this same process for estimating the R&D costs for gasoline engines which 

are shown in Table 5. We have used many of the same estimates for gasoline engines as for 

diesel engines with the exception that we have estimated only eight system threshold 

monitors for gasoline engines.b

 As shown in Table 5A, we have estimated that the algorithm 

development costs for gasoline engines will be zero since the manufacturers of gasoline 

engines (only Ford and General Motors have certified gasoline engines for over 14,000 

pound vehicles) have been complying with OBD requirements for over 10 years on their 

under 14,000 pound vehicles. We believe that the algorithms used in under 14,000 pound 

vehicles will be directly applicable to over 14,000 pound vehicles with only some adapting of 

those algorithms. The costs for adapting the existing algorithms to each engine family are 

shown in Table 5B where we have estimated the costs at $5 million. Note that our 2004 

model year certification database shows two over 14,000 pound engine families certified by 

General Motors and none certified by Ford. We have estimated that Ford will certify an 

engine family in future model years and, therefore, have estimated an average of 1.5 engine 

families per manufacturer. Table 5C shows the costs for applying algorithms to each 

remaining variant within the engine family. Again, as with diesel, we have estimated this 

cost at one-quarter the cost of first adapting an algorithm to the engine family. These efforts 

are estimated to result in another $5 million. All of these gasoline engine costs will be 

incurred in a manner analogous to that described above for diesel engines. 

b

 The eight threshold monitors for gasoline engines, based on our engineering judgement, would be: fuel 

system too rich; fuel system too lean; multiple cylinder random misfire; secondary air system low flow; catalyst 

conversion; EGR low flow; variable valve timing (VVT) above target; VVT below target; VVT slow response; 

and primary exhaust gas sensor slow response. As with diesel engines, we have estimated 50 percent to be 

EGR equipped with 50 percent being VVT equipped. 

18 
Final Technical Support Document; HDOBD Final Rule 

Table 5. R&D Costs for OBD Algorithm Development and Application – Gasoline Engines for Over 

14,000 Pound Applications 

(2007 dollars) 

A. Algorithm Development Costs weeks/monitor Cost/monitor # of monitors Total/Mfr Total

 System Threshold Monitors 

Engineer $ 

Technician $ 

Subtotal 

System Functional Monitors 

Engineer $ 

Technician $ 

Subtotal 

30 

15 

20 

5 

$69,000 

$21,000 

$90,000 

$46,000 

$7,000 

$53,000 

-

-

$0 

$0 

$0 

$0 

CCM Rationality Monitors 

Engineer $ 

Technician $ 

Subtotal 

CCM Continuity Monitors 

Engineer $ 

Technician $ 

Subtotal 

15 

1 

2 

0 

$34,000 

$1,000 

$35,000 

$5,000 

$0 

$5,000 

-

-

$0 

$0 

$0 

$0 

Total $0 $0 

B. Application Costs to each Family weeks/monitor Cost/monitor # of monitors Total/Family # families/mfr Total/Mfr Total

 System Threshold Monitors 

Engineer $ 

Technician $ 

Subtotal 

System Functional Monitors 

Engineer $ 

Technician $ 

Subtotal 

5 

10 

5 

10 

$11,000 

$14,000 

$25,000 

$11,000 

$14,000 

$25,000 

8 

42 

$200,000 

$1,050,000 

1.5 

1.5 

$300,000 

$1,575,000 

$600,000 

$3,150,000 

CCM Rationality Monitors 

Engineer $ 

Technician $ 

Subtotal 

Total 

3 

1 

$7,000 

$1,000 

$8,000 50 $400,000 

$1,650,000 

1.5 $600,000 

$2,475,000 

$1,200,000 

$4,950,000 

C. Application Costs to remaining Variants Total/Variant # variants/family # families/mfr Total/Mfr Total 

Total $413,000 4 1.5 $2,478,000 $4,956,000 

Closely associated with the costs shown in Table 4 and Table 5 would be costs associated 

with operating and maintaining the test cells required for testing and evaluating the OBD 

systems and associated algorithms. To determine these costs we projected that two types of 

test cell work would be done. The first would be actual emissions testing using a certified 

emissions test cell. The other would be performance and/or endurance testing done in a 

development test cell where OBD monitors could be evaluated against functional criteria 

rather than emissions criteria and where operating hours can be amassed far more cost 

efficiently than by using a certified emissions test cell. The costs associated with these 

different test cells were estimated at $770 per hour for an emissions test cell and $110 per 

hour for an endurance test cell. We also estimated that 90 percent of the test cell time for 

OBD development work would be done in an endurance test cell with the remaining 10 

percent being done in an emissions test cell. 

Table 6 shows the test cell costs we have estimated for diesel engines. Note that these 

costs represent the costs associated with operating existing test cells for the sake of meeting 

the OBD requirements. We are not projecting that any new test cells would have to be built. 

As shown in Table 6, we have estimated the test cell demand for algorithm development of a 

system threshold monitor at three weeks. Algorithm development of a system functional 

monitor was estimated to require two weeks of test cell time while a rationality monitor was 

estimated at one week. We have estimated no test cell demand for circuit continuity 

19 
Final Technical Support Document; HDOBD Final Rule 

monitors. We have used the same base estimates for the test cell demand associated with 

applying algorithms to individual engine families except that we have estimated the demand 

to be only 30 percent of that required for algorithm development. The same is true for 

applying engine family algorithms to individual variants except here we have estimated the 

demand to be only 10 percent of that required for initial algorithm development. 

Table 6 shows how these costs are incurred in preparation for compliance in the 2010 

model year and the 2013 model year. As stated above, 90 percent of the test cell demand— 

i.e., the total test weeks—would be met using an endurance test cell at $110 per hour while 

the remaining 10 percent of the demand would be met using an emissions test cell at $770 

per hour. Note that there would be no test cell demand for algorithm development beyond 

that incurred for 2010 since the same algorithms would be used for 2010 and later model 

years. Table 6A shows an estimated cost for test cell operation of $1.9 million per 

manufacturer or $19 million for the industry in preparation for the 2010 model year. These 

costs would be incurred over the four year period leading up to the 2010 model year. For the 

2013 model year when 100 percent compliance is required, the cost is estimated at $4.3 

million per manufacturer or $43 million total to be spread over the four year period leading 

up to the 2013 model year. The 2013 costs are shown in Table 6B. 

Table 7A and Table 7B show the analogous information for gasoline engines complying 

in the 2010 and 2013 model years, respectively. The table shows that we have estimated no 

costs—development or test cell—for developing monitoring algorithms for gasoline engines 

since the same algorithms as are used on under 14,000 pound vehicles can be used for over 

14,000 pound vehicles. The test cell costs for gasoline engines are estimated at $1.6 million 

for 2010 model year compliance and $780 thousand for 2013 model year compliance. As 

with the diesel costs, these costs are expected to be incurred over the four year period leading 

up to the first year of compliance. 

Table 8 and Table 9 summarize the estimated test cell demand per manufacturer for 

meeting the 2010 and the 2013 requirements. These summaries estimate that testing is 

conducted during 48 weeks in a given year. 

20 
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$0 $0 

Final Technical Support Document; HDOBD Final Rule 

Table 6. OBD R&D Test Cell Costs – Diesel Engines for Over 14,000 Pound Applications 

(2007 dollars) 

A. R&D Test Cell Costs - Diesel Cost for 2010 

Monitor Algorithms test wks # of monitors total test wks Costs/mfr 

System monitor - threshold 3 9 27.0 $190,000 System monitor - functional 2 41 82.0 $576,000 Rationality monitor 1 50 50.0 $351,000 Subtotal $1,117,000 $ per year for 4 years $279,250 

System monitor - functional 0.6 41 1.0 24.6 $173,000 Rationality monitor 0.3 50 1.0 15.0 $105,000 Subtotal $335,000 $ per year for 4 years $83,750 

Monitor Application to each engine family 

factor 30% # of monitors # families/mfr total test wks Costs/mfr System monitor - threshold 0.9 9 1.0 8.1 $57,000 

Monitor Application to each engine family variant 

factor 10% # of monitors # families/mfr additional variants total test wks Costs/mfr System monitor - threshold 0.3 9 1.0 4.0 10.8 $76,000 System monitor - functional 0.2 41 1.0 4.0 32.8 $230,000 Rationality monitor 0.1 50 1.0 4.0 20.0 $140,000 Subtotal $446,000 $ per year for 4 years $111,500 

Total R&D Test Cell Costs 

$ per year for 4 years 

$1,898,000 

$474,500 

B. R&D Test Cell Costs - Diesel 

Monitor Algorithms 

System monitor - threshold System monitor - functional Rationality monitor Subtotal $ per year for 4 years 

test wks 

3 

2 

1 

# of monitors 

0 0 0 

Costs for 2013 

total test wks Costs/mfr 

Monitor Application to each engine family 

factor 30% # of monitors # families/mfr total test wks Costs/mfr System monitor - threshold 0.9 9 5.5 44.6 $313,000 System monitor - functional 0.6 41 5.5 135.3 $950,000 Rationality monitor 0.3 50 5.5 82.5 $580,000 Subtotal $1,843,000 $ per year for 4 years $460,750 

Monitor Application to each engine family variant 

factor 10% # of monitors # families/mfr additional variants total test wks Costs/mfr System monitor - threshold 0.3 9 5.5 4.0 59.4 $417,000 System monitor - functional 0.2 41 5.5 4.0 180.4 $1,267,000 Rationality monitor 0.1 50 5.5 4.0 110.0 $773,000 Subtotal $2,457,000 $ per year for 4 years 

Total R&D Test Cell Costs $4,300,000 

$ per year for 4 years $1,075,000 

21 
- $0

- $0

- $0

$0 $0 

- $0

- $0

- $0

$0 $0 

Final Technical Support Document; HDOBD Final Rule 

Table 7. OBD R&D Test Cell Costs – Gasoline Engines for Over 14,000 Pound Applications 

(2007 dollars) 

A. R&D Test Cell Costs - Gasoline Cost for 2010 

Monitor Algorithms test wks # of monitors total test wks Costs/mfr # 

System monitor - threshold 

System monitor - functional 

Rationality monitor 

Subtotal $ per year for 4 years 

3 

2 

1 

0 

0 

0 

Monitor Application to each engine family 

factor System monitor - threshold 

System monitor - functional 0.6 42 1.0 25.2 $177,000 

Rationality monitor 0.3 50 1.0 15.0 $105,000 

Subtotal $333,000 $ per year for 4 years $83,250 

30% # of monitors # families/mfr total test wks Costs/mfr # 

0.9 8 1.0 7.2 $51,000 

Monitor Application to each engine family variant 

factor 10% # of monitors # families/mfr additional variants total test wks Costs/mfr # System monitor - threshold 0.3 8 1.0 4.0 9.6 $67,000 

System monitor - functional 0.2 42 1.0 4.0 33.6 $236,000 

Rationality monitor 0.1 50 1.0 4.0 20.0 $140,000 

Subtotal $443,000 $ per year for 4 years $110,750 

Total R&D Test Cell Costs 

$ per year for 4 years 

$776,000 $194,000 

B. R&D Test Cell Costs - Gasoline 

Monitor Algorithms 

System monitor - threshold 

System monitor - functional 

Rationality monitor 

Subtotal $ per year for 4 years 

test wks 

3 

2 

1 

# of monitors 

0 

0 

0 

Costs for 2013 

total test wks Costs/mfr # 

Monitor Application to each engine family 

factor 30% # of monitors # families/mfr total test wks Costs/mfr # System monitor - threshold 0.9 8 0.5 3.6 $25,000 

System monitor - functional 0.6 42 0.5 12.6 $89,000 

Rationality monitor 0.3 50 0.5 7.5 $53,000 

Subtotal $167,000 $ per year for 4 years $41,750 

Monitor Application to each engine family variant 

factor 10% # of monitors # families/mfr additional variants total test wks Costs/mfr # System monitor - threshold 0.3 8 0.5 4.0 4.8 $34,000 

System monitor - functional 0.2 42 0.5 4.0 16.8 $118,000 

Rationality monitor 0.1 50 0.5 4.0 10.0 $70,000 

Subtotal $222,000 $ per year for 4 years $55,500 

Total R&D Test Cell Costs $389,000 

$ per year for 4 years $97,250 

22 
Final Technical Support Document; HDOBD Final Rule 

Table 8. OBD R&D Test Cell Demand per Manufacturer – Diesel Engines for Over 14,000 Pound 

Applications 

For 2010 

A. R&D Test Cell Demand - Diesel Total test wks CVS cell test wks Endurance cell test wks 

Monitor Algorithms 159.0 15.9 143.1 

Monitor Application to each engine family 47.7 4.8 42.9 

Monitor Application to each engine family variant 63.6 6.4 57.2 

Total 270.3 27.0 243.3 

Cells needed per mfr 0.6 5.1 

Cells needed per mfr per each of 4 years 0.1 1.3 

For 2013 

B. R&D Test Cell Demand - Diesel Total test wks CVS cell test wks Endurance cell test wks 

Monitor Algorithms - - -

Monitor Application to each engine family 262.4 26.2 236.1 

Monitor Application to each engine family variant 349.8 35.0 314.8 

Total 612.2 61.2 550.9 

Cells needed per mfr 1.3 11.5 

Cells needed per mfr per each of 4 years 0.3 2.9 

Table 9. OBD R&D Test Cell Demand per Manufacturer – Gasoline Engines for Over 14,000 Pound 

Applications 

For 2010 

A. R&D Test Cell Demand - Gasoline Total test wks CVS cell test wks Endurance cell test wks 

Monitor Algorithms - - -

Monitor Application to each engine family 47.4 4.7 42.7 

Monitor Application to each engine family variant 63.2 6.3 56.9 

Total 110.6 11.1 99.5 

Cells needed per mfr 0.2 2.1 

Cells needed per mfr per each of 4 years 0.1 0.5 

For 2013 

B. R&D Test Cell Demand - Gasoline Total test wks CVS cell test wks Endurance cell test wks 

Monitor Algorithms - - -

Monitor Application to each engine family 23.7 2.4 21.3 

Monitor Application to each engine family variant 31.6 3.2 28.4 

Total 55.3 5.5 49.8 

Cells needed per mfr 0.1 1.0 

Cells needed per mfr per each of 4 years 0.0 0.3 

These R&D costs—algorithm development, algorithm application, and test cell—are 

summarized in Table 10 for both diesel and gasoline engines. The net present value of the 

estimated R&D costs through 2035 is $298 million using a three percent discount rate and $252 

million using a seven percent discount rate. 

23 
$0

$0$0$0

$0 $0$0 $0$0 $0$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 

$0$0

Final Technical Support Document; HDOBD Final Rule 

Table 10. Summary of OBD R&D Costs – Diesel and Gasoline Engines for Over 14,000 Pound Applicatio

(2007 dollars) 

Year CY 

Diesel Gasoline 

R&D-Algorithms R&D-Application R&D-Test Cell Subtotal R&D R&D-Algorithms R&D-Application R&D-Test Cell Su

1 2006 $12,833,000 $8,255,000 $4,745,000 $25,833,000 $1,651,000 $388,000 2 2007 $12,833,000 $8,255,000 $4,745,000 $25,833,000 $1,651,000 $388,000 3 2008 $12,833,000 $8,255,000 $4,745,000 $25,833,000 $1,651,000 $388,000 4 2009 $12,833,000 $53,658,000 $15,495,000 $81,986,000 $2,477,000 $583,000 5 2010 $45,403,000 $10,750,000 $56,153,000 $826,000 $195,000 6 2011 $45,403,000 $10,750,000 $56,153,000 $826,000 $195,000 7 2012 $45,403,000 $10,750,000 $56,153,000 $826,000 $195,000 8 2013 9 2014 

10 2015 11 2016 12 2017 13 2018 14 2019 15 2020 16 2021 17 2022 18 2023 19 2024 20 2025 21 2026 22 2027 23 2028 24 2029 25 2030 26 2031 27 2032 28 2033 29 2034 30 2035 

NPV @ 3% $47,702,000 $185,131,000 $54,206,000 $287,038,000 $8,947,000 $2,106,000 $NPV @ 7% $43,468,000 $153,500,000 $45,796,000 $242,763,000 $7,876,000 $1,853,000 

24 
Final Technical Support Document; HDOBD Final Rule 

b. Certification and Production Evaluation Testing Costs 

As noted above, the certification costs include the costs associated with testing of durability 

data vehicles (i.e., the OBD parent engines), the costs associated with generating the “limit” parts 

that are required to demonstrate OBD detection at or near the applicable emissions thresholds, 

and the costs associated with generating the necessary certification documentation. 

Cost of OBD Limit Parts 

We look first at the costs associated with generating limit parts for certification 

demonstration testing. These are the parts used to demonstrate OBD detection at or near the 

applicable emissions thresholds. Such parts can be very difficult to generate because of the 

difficulties associated with deteriorating parts just the right amount—not so much that the 

thresholds are grossly exceeded thereby making the demonstration test somewhat meaningless 

and not so little that emissions remain well below the thresholds. 

Table 11 shows the costs we have estimated for the limit parts needed for diesel engine 

demonstration testing. To arrive at these costs, we estimated the part costs of aftertreatment 

devices based on our 2007/2010 highway heavy-duty rule and our recent nonroad Tier 4 rule. 

However, since those costs represented costs of new parts being mass produced, we doubled the 

costs here to represent the higher costs associated with orders to suppliers consisting of only one 

or two parts. Fuel system costs were estimated to include costs for injectors, pressure regulators, 

etc. The exhaust gas sensor costs estimate NOx sensors and estimate that these are ordered (and 

costed) in sets of two. We estimated the costs for a typical light-heavy, medium-heavy, and 

heavy-heavy engine assuming 6, 8, and 14 liter displacements, respectively. We sales weighted 

these costs using the projected sales data from our 2004 model year certification database 

excluding California sales and excluding those engines certified for use in vehicles under 14,000 

pounds. We have estimated that two parts would be needed to account for possible errors and/or 

the need for parts to demonstrate both a high and a low failure (e.g., EGR flow high/EGR flow 

low). For variable valve timing (VVT) costs, we have estimated these based on input from 

industry and not based on our prior analyses which did not consider costs for VVT systems. As 

shown in Table 11, multiplying through and including the percent of engines we expect will need 

the particular limit parts, results in limit parts cost of $21,300 for each diesel engine undergoing 

demonstration testing. 

25 
Final Technical Support Document; HDOBD Final Rule 

Table 11. Cost for OBD Certification Demonstration Limit Parts – Diesel Engines for Over 14,000 Pound 

Applications 

(2007 dollars) 

Diesel Engines 

Light-heavy 

14-19.5K Medium-heavy Heavy-heavy Sales Weighted 

Parts needed 

(incl errors) 

Percent 

needing part Fleet weighted 

Displacement (liters) 6 8 14 

2004 Projected Sales less CA sales 21,695 361,393 231,434 614,522 

NOx Adsorber $1,646 $2,195 $3,622 $2,700 2 50% $2,700 

SCR $1,646 $2,195 $3,622 $2,700 2 50% $2,700 

DPF $2,744 $3,512 $6,147 $4,500 2 100% $9,000 

Fuel system $1,372 $1,372 $1,646 $1,500 2 100% $3,000 

Exhaust gas sensors $220 $220 $220 $200 2 100% $400 

Turbo $615 $626 $692 $700 2 100% $1,400 

EGR System $406 $483 $724 $600 2 50% $600 

VVT $1,646 $1,646 $1,646 $1,500 2 50% $1,500 

Total for Limit Parts $21,300 

We have not estimated costs associated with generating limit parts for gasoline engines 

because we do not expect that over 14,000 pound engines will be used for certification 

demonstration. Instead, we expect that manufacturers will demonstrate their OBD systems using 

an engine or vehicle in the under 14,000 pound range and then provide documentation in their 

certification package showing how their over 14,000 pound engine is represented by the under 

14,000 pound demonstration as allowed by the proposed program. While this may also be the 

case for some diesel engine manufacturers, we have chosen to be conservative in our estimates 

by assuming that all diesel demonstrations will be over 14,000 pounds. 

We have also estimated costs for aging these limit parts to the point where emissions are 

near the OBD thresholds. These costs were not included in our draft cost analysis but have been 

included in the final analysis (see the Summary and Analysis of Comments document Section 

VI.B). To estimate these costs, we have considered the final requirement for aging of 

aftertreatment devices which requires half life aging in early years and full life aging in later 

years. On average, we have estimated this at 80 percent of uselife life given a belief that 

manufacturers will be able to demonstrate that, for OBD, such aging is representative of full life. 

We have also used a sales weighted full useful life of 335,000 miles and sales weighted MPG of 

7, and an endurance test cell cost of $110/hour to arrive at the following costs: 

Fuel costs: (335,000 miles x 80%)/7 MPG x $3/gallon = $115,000 per parent engine 

Test cell costs: (335,000 miles x 80%)/30 MPH x $110/hr = $981,000 per parent engine. 

The total costs for limit part aging being $1.1 million per parent engine. We have added 

these costs to the costs of limit parts in the final analysis. As a result, in the final cost analysis, 

limit part costs consist of the limit part hardware and the limit part aging. 

Note that we believe this to be an overestimation of the costs associated with aging of limit 

parts. We expect that manufacturers will use other means to “age” the parts to the OBD 

thresholds (e.g., rapid aging, oven baking, etc.) and will not actually age the parts on an engine 

dynamometer for 335,000 miles. However, such dynamometer aging is one potential method, 

26 
Final Technical Support Document; HDOBD Final Rule 

albeit a worst case method, and provides a practical means of estimating the costs. In the end, 

the costs we have estimated are worst case and will almost certainly be lower. 

We have estimated that these costs for limit parts will be incurred every three years going 

forward. In 2010, one engine family per manufacturer will have to be demonstrated and in 2013 

we expect another two engine families per manufacturer to undergo demonstration testing (for 

diesels). We would then expect engine families to be carried-over for three years at which time 

another three engines would be demonstrated, etc. This is an over simplification of the carryover provisions of our certification program, but it serves our purpose here and does not under 

estimate the costs but rather impacts only when those costs are incurred. We use this same 

simplifying assumption throughout our analysis of certification and production evaluation testing 

costs as is shown in Table 12 which shows all our estimated certification and production 

evaluation testing costs for diesel engines and Table 13 which shows the analogous costs for 

gasoline engines. 

27 
$0 $0 $0 $0 $0 $0 

$0 $0 $0 $0 $0 $0 

$0 $0 $0 $0 $0 $0 

$0 $0 

$0 $0 $0 $0$0 $0 $0 $0 $0 $0

$0 $0

$0 $0 $0 $0$0 $0 $0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0 $0 $0

Final Technical Support Document; HDOBD Final Rule 

Table 12. OBD Certification and Production Evaluation Testing Costs – Diesel Engines for Over 14,000 Pound App

(2007 dollars) 

Certification Demonstration Testing Related Certification Documentation Related Production Evaluation Testing Related 

Year CY 

# of parent 

test engines 

Costs for Limit 

Parts 

DDV Testing 

Costs Total DDV Costs 

# of 

parent 

families 

# 

remaining 

families 

Cert 

Documentation 

Costs 

PE Testing - Scan Tool PE Testing - Monitors PE Testing - Ratio

# of engine 

families for 

testing PE Costs 

# of OBD 

Groups 

tested 

PE Costs (incl 

vehicle rental) 

# of 

monitoring 

groups 

tested PE Cos

1 2006 0 0 0 0 0 0 

2 2007 0 0 0 0 0 0 

3 2008 0 0 0 0 0 0 

4 2009 10 $11,173,000 $553,000 $11,726,000 10 0 $55,000 0 0 0 

5 2010 0 0 0 10 $23,000 10 $211,000 30 $8,6 2011 0 0 0 0 0 30 $8,

7 2012 20 $22,346,000 $1,106,000 $23,452,000 20 45 $233,000 0 0 30 $8,8 2013 0 0 0 55 $126,000 20 $280,000 60 $15,9 2014 0 0 0 0 0 60 $15,

10 2015 30 $33,519,000 $1,660,000 $35,179,000 30 35 $261,000 0 0 60 $15,11 2016 0 0 0 65 $149,000 30 $348,000 60 $15,

12 2017 0 0 0 0 0 60 $15,

13 2018 30 $33,519,000 $1,660,000 $35,179,000 30 35 $261,000 0 0 60 $15,14 2019 0 0 0 65 $149,000 30 $348,000 60 $15,

15 2020 0 0 0 0 0 60 $15,

16 2021 30 $33,519,000 $1,660,000 $35,179,000 30 35 $261,000 0 0 60 $15,17 2022 0 0 0 65 $149,000 30 $348,000 60 $15,

18 2023 0 0 0 0 0 60 $15,

19 2024 30 $33,519,000 $1,660,000 $35,179,000 30 35 $261,000 0 0 60 $15,20 2025 0 0 0 65 $149,000 30 $348,000 60 $15,

21 2026 0 0 0 0 0 60 $15,

22 2027 30 $33,519,000 $1,660,000 $35,179,000 30 35 $261,000 0 0 60 $15,23 2028 0 0 0 65 $149,000 30 $348,000 60 $15,

24 2029 0 0 0 0 0 60 $15,

25 2030 30 $33,519,000 $1,660,000 $35,179,000 30 35 $261,000 0 0 60 $15,26 2031 0 0 0 65 $149,000 30 $348,000 60 $15,

27 2032 0 0 0 0 0 60 $15,

28 2033 30 $33,519,000 $1,660,000 $35,179,000 30 35 $261,000 0 0 60 $15,29 2034 0 0 0 65 $149,000 30 $348,000 60 $15,

30 2035 0 0 0 0 0 60 $15,

NPV @ 3% $164,018,000 $8,122,000 $172,140,000 $1,297,000 $706,000 $1,773,000 $221,NPV @ 7% $92,794,000 $4,595,000 $97,388,000 $735,000 $382,000 $996,000 $121,

28 
$0 $0 $0 $0 $0 $0 

$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0

$0 $0 $0 $0 $0 $0$0 $0 $0 $0 $0

$0 $0 $0 $0

$0 $0 $0 $0 $0 $0

$0 $0 $0 $0 $0

$0 $0 $0 $0$0 $0 $0 $0 $0 $0

$0 $0 $0 $0 $0

$0 $0 $0 $0$0 $0 $0 $0 $0 $0

$0 $0 $0 $0 $0

$0 $0 $0 $0$0 $0 $0 $0 $0 $0

$0 $0 $0 $0 $0

$0 $0 $0 $0$0 $0 $0 $0 $0 $0

$0 $0 $0 $0 $0

$0 $0 $0 $0$0 $0 $0 $0 $0 $0

$0 $0 $0 $0 $0

$0 $0 $0 $0

$0 $0 $0 $0 $0 $0

$0 $0 $0 $0 $0

$0 $0 $0 $0$0 $0 $0 $0 $0 $0$0 $0 $0$0 $0 $0

Final Technical Support Document; HDOBD Final Rule 

Table 13. OBD Certification and Production Evaluation Testing Costs – Gasoline Engines for Over 14,000 Pound Ap

(2007 dollars) 

Certification Demonstration Testing Related Certification Documentation Related Production Evaluation Testing Related 

Year CY 

# of 

parent 

test 

engines 

Costs for 

Limit Parts 

DDV Testing 

Costs 

Total DDV 

Costs 

# of parent 

families 

# remaining 

families 

Cert 

Documentation 

Costs 

PE Testing - Scan Tool PE Testing - Monitors PE Testing - Ratios 

# of engine 

families for 

testing PE Costs 

# of OBD 

Groups 

tested 

PE Costs (incl 

vehicle rental) 

# of 

monitoring 

groups 

tested PE Cos

1 2006 0 0 0 0 0 0 2 2007 0 0 0 0 0 0 3 2008 0 0 0 0 0 0 4 2009 0 0 0 0 0 0 5 2010 0 0 0 2 $5,000 2 $42,000 6 $2,0

6 2011 0 0 0 0 0 6 $2,07 2012 0 0 3 $8,000 0 0 6 $2,0

8 2013 0 0 0 1 $2,000 1 $21,000 6 $2,0

9 2014 0 0 0 0 0 6 $2,0

10 2015 0 0 3 $8,000 0 0 6 $2,0

11 2016 0 0 0 3 $7,000 3 $49,000 6 $2,012 2017 0 0 0 0 0 6 $2,0

13 2018 0 0 3 $8,000 0 0 6 $2,0

14 2019 0 0 0 3 $7,000 3 $49,000 6 $2,015 2020 0 0 0 0 0 6 $2,0

16 2021 0 0 3 $8,000 0 0 6 $2,0

17 2022 0 0 0 3 $7,000 3 $49,000 6 $2,018 2023 0 0 0 0 0 6 $2,0

19 2024 0 0 3 $8,000 0 0 6 $2,0

20 2025 0 0 0 3 $7,000 3 $49,000 6 $2,021 2026 0 0 0 0 0 6 $2,0

22 2027 0 0 3 $8,000 0 0 6 $2,0

23 2028 0 0 0 3 $7,000 3 $49,000 6 $2,024 2029 0 0 0 0 0 6 $2,0

25 2030 0 0 3 $8,000 0 0 6 $2,0

26 2031 0 0 0 3 $7,000 3 $49,000 6 $2,0

27 2032 0 0 0 0 0 6 $2,0

28 2033 0 0 3 $8,000 0 0 6 $2,0

29 2034 0 0 0 3 $7,000 3 $49,000 6 $2,030 2035 0 0 0 0 0 6 $2,0

NPV @ 3% $39,000 $33,000 $246,000 $32,0NPV @ 7% $22,000 $18,000 $138,000 $18,0

29 
Final Technical Support Document; HDOBD Final Rule 

Focusing first on Table 12, the limit parts costs are first incurred in 2009 in advance of the 

2010 model year. The limit parts cost estimate for diesels shown in Table 11 ($21,300 per 

engine) plus the aging component of $1.1 million per engine is incurred on one engine family for 

each of 10 engine manufacturers for a total cost that year of $11 million. This process is carried 

forward every three years as discussed above. As noted, for gasoline engines, Table 13 shows no 

limit parts costs or demonstration testing costs. 

OBD Certification Demonstration Testing Costs 

For costs associated with the actual demonstration testing of OBD parent engines (diesel 

only), we have estimated that two OBD threshold monitors can be demonstrated during a given 

day of testing in an emissions test cell. With our estimate of 9 threshold monitors per engine, 

this means 9 days of testing in an emissions test cell that costs $770 dollars per hour or $6,100 

per day to operate. The OBD parent engine, or durability data vehicle (DDV), demonstration 

testing costs were then calculated by multiplying the test days per engine (9) by the dollars per 

day ($6,100) and again by the number of demonstration engines being demonstrated for the 

given model year. The result in 2009 is $553,000 for all 10 engine manufacturers which is 

incurred one year in advance of implementation because they are certification costs. These costs 

change depending on the number of engine families undergoing demonstration testing. 

OBD Certification Documentation Costs 

For certification documentation costs, we have estimated that a certification documentation 

package for an OBD parent engine would cost $5,500 while it would cost $2,700 for a non-OBD 

parent engine (i.e., an OBD child rating). We consider this to be a conservative estimate since 

most child ratings would very likely incur no costs since it would be part of an OBD group 

represented by the OBD parent engine and should, therefore, require no further certification 

documentation. Our certification database for the 2004 model year showed 65 diesel engine 

families and three gasoline engine families in the over 14,000 pound range. Multiplying the 

expected number of OBD parent engines and child engines being certified for each given year by 

the estimated costs to generate the certification documentation packages results in the costs 

shown in Table 12 and Table 13. 

OBD Production Evaluation Testing Costs 

Also shown are costs for production evaluation (PE) testing. The required production 

evaluation testing consists of three elements. The first of these is testing to ensure that 

engines/vehicles comply with the standardization requirements of the OBD rule. This is done by 

connecting a scan tool to a production vehicle to ensure that the onboard systems communicate 

properly to an off board device (e.g., a scan tool). We would expect this testing to be done as 

vehicles roll off the vehicle assembly line. The second element of PE testing is testing to ensure 

that the OBD monitors are functioning properly. This is done by implanting or simulating 

malfunctions and determining whether or not the OBD monitors run and detects them. This 

testing does not involve any actual emissions testing. We would expect this testing to be done on 

one to three production vehicles but required test beyond one vehicle could be done on 

30 
Final Technical Support Document; HDOBD Final Rule 

production engines rather than production vehicles. The third element of PE testing is testing to 

ensure that OBD monitors are running and making diagnostic decisions with sufficient frequency 

in the real world. This is done by scanning the stored OBD information contained in actual inuse vehicles and noting the performance ratios for various non-continuous monitors. Since the 

production evaluation testing is a post-certification requirement, the costs would be incurred 

either as new engines/vehicles are rolling off the assembly line or during the six to 12 months 

following introduction into commerce. 

OBD Production Evaluation Testing Costs – Standardization Requirements 

To estimate the PE testing costs for verifying the standardization requirements, we have 

conservatively estimated that the actual test would take four hours and that for each engine 

family sold the maximum of 10 vehicles would be tested. We have also conservatively estimated 

that the testing would be done by an engineer at $110,000 per year rather than the more likely 

choice of a technician at $66,000 per year. Multiplying the number of engine families by the 

number of vehicles tested per family, the hours per test, and the engineer’s cost per hour results 

in the yearly estimated costs. This cost—shown as “PE testing - scan tool” in the tables—is 

estimated at $23,000 for diesel engines in 2010 and $5,000 for gasoline engines in 2010. These 

costs would be incurred on newly introduced OBD-compliant engine families. Therefore, we 

have estimated costs for testing the engine families from which the OBD parent engine has been 

chosen. We have also included costs for future model years assuming that most engines undergo 

enough changes over a three year period to nullify the ability to carry-over from a prior year’s 

certification. When that occurs, we would expect the PE scan tool testing to be done. 

OBD Production Evaluation Testing Costs – Monitor Verification 

To estimate the PE testing costs for verifying monitors, we have first been conservative by 

estimating that each manufacturer would conduct the testing for each of three OBD groups. This 

overestimates these costs because some manufacturers will only have to conduct the testing on 

one, and others on two, OBD groups because they do not sell enough different engine families to 

require testing of three. We have also estimated that, as allowed by the proposed rule, the first 

OBD group tested would have to be tested using a production vehicle while the remaining OBD 

groups tested would use a production engine. We have estimated the time required to conduct 

the testing at three weeks and that the testing would be done by an engineer costing $110,000 per 

year. We have also estimated that it would cost $11,000 to rent or otherwise acquire a vehicle 

for testing while acquiring an engine would not cost the engine manufacturer anything. Lastly, 

we have estimated travel costs at $3,300 dollars for testing done on a production vehicle while 

travel costs for testing on production engines would be zero. The certification and production 

engine testing cost tables show—in the columns under “PE testing – monitors”—the number of 

OBD groups undergoing this testing in given years. The 10 shown for 2010 represent one engine 

tested from each OBD compliant engine family by each of 10 manufacturers. In 2013, we 

require all engine families to comply but only up to two new engine families must undergo 

certification demonstration testing and, consequently, PE testing for monitors. For simplicity, as 

stated elsewhere, we have estimated three new parent engines per manufacturer undergo 

certification demonstration testing every three years and, consequently, they undergo PE testing 

for monitors. 

31 
Final Technical Support Document; HDOBD Final Rule 

OBD Production Evaluation Testing Costs – Performance Ratios 

To estimate the PE testing costs for evaluating in-use performance ratios, we have first 

conservatively estimated that every OBD monitoring group would have to test the maximum of 

15 vehicles. An OBD monitoring group is defined first by emissions control architecture (i.e., 

combination of EGR, turbo, and aftertreatment devices) and secondly by application type (i.e., 

line haul, urban delivery, other). We have estimated that each manufacturer would have two 

emissions control architectures and engines sold into each of the three application types. As a 

result, there would be six monitoring groups per each of 10 different manufacturers for 60 

monitoring groups being tested. This is true except for the 2010 to 2012 model years when, 

since only one engine family is compliant, we have assumed only one emissions control 

architecture and, therefore, only three OBD monitoring groups for each of 10 manufacturers for 

30 total. We have also estimated that the test itself—simply connecting a scan tool and 

downloading the performance ratio data—would take half an hour to complete by a technician 

costing $66,000 per year. We have been conservative in our estimate by including costs for this 

testing in every year even though we would expect that data could be carried over from one year 

to the next once we are sure that monitors are indeed running at sufficient frequency in-use. 

Table 14 shows the cost streams presented above for all fixed costs. The fixed costs 

consist of R&D, certification, and production evaluation testing costs. Also shown are the 30 

year net present values at a three percent discount rate which are $463 million for diesel, $11 

million for gasoline and $475 million for the entire industry. The total fixed costs are also shown 

on a per engine basis using the projected sales shown in Table 3. 

32 
$0 $0

$0 $0$0 $0

$0

$0 $0

$0 $0$0 $0

$0 $0

$0 $0$0 $0

$0 $0

$0 $0$0 $0

$0 $0

$0 $0$0 $0

$0 $0

$0 $0$0 $0

$0 $0

$0 $0$0 $0

$0 $0

$0 $0$0 $0

$0 $0

$0 $0

Final Technical Support Document; HDOBD Final Rule 

Table 14. Total OBD Fixed Costs – Diesel and Gasoline Engines for Over 14,000 Pound Applications 

(2007 dollars) 

Year CY 

Diesel Gasoline 

R&D Cert/PE Testing Subtotal Projected Sales $/engine R&D Cert/PE Testing Subtotal Projected Sales 

1 2006 $25,833,000 $25,833,000 639,103 $40 $2,039,000 $2,039,000 40,976 2 2007 $25,833,000 $25,833,000 651,393 $40 $2,039,000 $2,039,000 41,764 3 2008 $25,833,000 $25,833,000 663,684 $39 $2,039,000 $2,039,000 42,552 4 2009 $81,986,000 $11,781,000 $93,767,000 675,974 $139 $3,060,000 $3,060,000 43,340 5 2010 $56,153,000 $242,000 $56,395,000 688,265 $82 $1,021,000 $49,000 $1,070,000 44,128 6 2011 $56,153,000 $8,000 $56,161,000 700,555 $80 $1,021,000 $2,000 $1,023,000 44,916 7 2012 $56,153,000 $23,693,000 $79,846,000 712,846 $112 $1,021,000 $10,000 $1,031,000 45,704 8 2013 $421,000 $421,000 725,136 $1 $25,000 $25,000 46,492 

9 2014 $15,000 $15,000 737,426 $0 $2,000 $2,000 47,280 

10 2015 $35,455,000 $35,455,000 749,717 $47 $10,000 $10,000 48,068 

11 2016 $512,000 $512,000 762,007 $1 $58,000 $58,000 48,856 

12 2017 $15,000 $15,000 774,298 $0 $2,000 $2,000 49,644 13 2018 $35,455,000 $35,455,000 786,588 $45 $10,000 $10,000 50,432 

14 2019 $512,000 $512,000 798,879 $1 $58,000 $58,000 51,220 

15 2020 $15,000 $15,000 811,169 $0 $2,000 $2,000 52,008 16 2021 $35,455,000 $35,455,000 823,459 $43 $10,000 $10,000 52,796 

17 2022 $512,000 $512,000 835,750 $1 $58,000 $58,000 53,584 

18 2023 $15,000 $15,000 848,040 $0 $2,000 $2,000 54,372 19 2024 $35,455,000 $35,455,000 860,331 $41 $10,000 $10,000 55,160 

20 2025 $512,000 $512,000 872,621 $1 $58,000 $58,000 55,948 

21 2026 $15,000 $15,000 884,912 $0 $2,000 $2,000 56,736 22 2027 $35,455,000 $35,455,000 897,202 $40 $10,000 $10,000 57,524 

23 2028 $512,000 $512,000 909,493 $1 $58,000 $58,000 58,312 

24 2029 $15,000 $15,000 921,783 $0 $2,000 $2,000 59,100 25 2030 $35,455,000 $35,455,000 934,073 $38 $10,000 $10,000 59,888 

26 2031 $512,000 $512,000 946,364 $1 $58,000 $58,000 60,676 

27 2032 $15,000 $15,000 958,654 $0 $2,000 $2,000 61,464 28 2033 $35,455,000 $35,455,000 970,945 $37 $10,000 $10,000 62,252 

29 2034 $512,000 $512,000 983,235 $1 $58,000 $58,000 63,040 

30 2035 $15,000 $15,000 995,526 $0 $2,000 $2,000 63,828 

NPV @ 3% $287,038,000 $176,137,000 $463,175,000 $11,052,000 $350,000 $11,402,000 NPV @ 7% $242,763,000 $99,623,000 $342,386,000 $9,730,000 $197,000 $9,926,000 

33 
$0 $0

$0 $0

$0 $0

$0 $0

Final Technical Support Document; HDOBD Final Rule 

3.1.3 Total Costs 

Combining the variable cost streams shown in Table 3 and the fixed costs streams shown in 

Table 14 results in the total estimated costs for the over 14,000 pound proposed OBD 

requirements. The results are shown in Table 15. As shown, the 30 year net present value at a 

three percent discount rate is estimated at $1.2 billion with the majority of those costs being for 

new hardware in the form of more powerful engine and emissions control system computers. 

Note that the per engine costs shown in Table 15 use the engine sales estimates shown in Table 3 

without accounting for any phase-in (i.e., the costs have been divided by the total new engine 

sales rather than dividing by the fraction of new engine sales that are compliant). 

Table 15. Total Estimated OBD Costs – Diesel and Gasoline Engines for Over 14,000 Pound Applications 

(2007 dollars) 

Year CY 

Diesel Gasoline 

Variable Fixed Subtotal Variable Fixed Subtotal Total Costs 

1 2006 $25,833,000 $25,833,000 $2,039,000 $2,039,000 $27,872,000 

2 2007 $25,833,000 $25,833,000 $2,039,000 $2,039,000 $27,872,000 

3 2008 $25,833,000 $25,833,000 $2,039,000 $2,039,000 $27,872,000 

4 2009 $93,767,000 $93,767,000 $3,060,000 $3,060,000 $96,827,000 

5 2010 $14,852,000 $56,395,000 $71,247,000 $1,164,000 $1,070,000 $2,234,000 $73,481,000 

6 2011 $15,117,000 $56,161,000 $71,278,000 $1,185,000 $1,023,000 $2,208,000 $73,486,000 

7 2012 $15,382,000 $79,846,000 $95,228,000 $1,205,000 $1,031,000 $2,236,000 $97,464,000 

8 2013 $43,646,000 $421,000 $44,067,000 $3,244,000 $25,000 $3,269,000 $47,336,000 

9 2014 $44,385,000 $15,000 $44,400,000 $3,299,000 $2,000 $3,301,000 $47,701,000 

10 2015 $45,125,000 $35,455,000 $80,580,000 $3,354,000 $10,000 $3,364,000 $83,944,000 

11 2016 $43,356,000 $512,000 $43,868,000 $3,248,000 $58,000 $3,306,000 $47,174,000 

12 2017 $44,055,000 $15,000 $44,070,000 $3,301,000 $2,000 $3,303,000 $47,373,000 

13 2018 $44,754,000 $35,455,000 $80,209,000 $3,353,000 $10,000 $3,363,000 $83,572,000 

14 2019 $45,454,000 $512,000 $45,966,000 $3,405,000 $58,000 $3,463,000 $49,429,000 

15 2020 $46,153,000 $15,000 $46,168,000 $3,458,000 $2,000 $3,460,000 $49,628,000 

16 2021 $46,852,000 $35,455,000 $82,307,000 $3,510,000 $10,000 $3,520,000 $85,827,000 

17 2022 $47,551,000 $512,000 $48,063,000 $3,563,000 $58,000 $3,621,000 $51,684,000 

18 2023 $48,251,000 $15,000 $48,266,000 $3,615,000 $2,000 $3,617,000 $51,883,000 

19 2024 $48,950,000 $35,455,000 $84,405,000 $3,667,000 $10,000 $3,677,000 $88,082,000 

20 2025 $49,649,000 $512,000 $50,161,000 $3,720,000 $58,000 $3,778,000 $53,939,000 

21 2026 $50,349,000 $15,000 $50,364,000 $3,772,000 $2,000 $3,774,000 $54,138,000 

22 2027 $51,048,000 $35,455,000 $86,503,000 $3,825,000 $10,000 $3,835,000 $90,338,000 

23 2028 $51,747,000 $512,000 $52,259,000 $3,877,000 $58,000 $3,935,000 $56,194,000 

24 2029 $52,446,000 $15,000 $52,461,000 $3,929,000 $2,000 $3,931,000 $56,392,000 

25 2030 $53,146,000 $35,455,000 $88,601,000 $3,982,000 $10,000 $3,992,000 $92,593,000 

26 2031 $53,845,000 $512,000 $54,357,000 $4,034,000 $58,000 $4,092,000 $58,449,000 

27 2032 $54,544,000 $15,000 $54,559,000 $4,086,000 $2,000 $4,088,000 $58,647,000 

28 2033 $55,244,000 $35,455,000 $90,699,000 $4,139,000 $10,000 $4,149,000 $94,848,000 

29 2034 $55,943,000 $512,000 $56,455,000 $4,191,000 $58,000 $4,249,000 $60,704,000 

30 2035 $56,642,000 $15,000 $56,657,000 $4,244,000 $2,000 $4,246,000 $60,903,000 

NPV @ 3% $685,964,000 $463,175,000 $1,149,139,000 $51,463,000 $11,402,000 $62,865,000 $1,212,004,000 

NPV @ 7% $363,769,000 $342,386,000 $706,155,000 $27,315,000 $9,926,000 $37,241,000 $743,396,000 

Table 16 shows these costs on a per engine basis by combining the per engine costs shown 

in Table 3 (variable costs) and Table 14 (fixed costs). 

34 
Final Technical Support Document; HDOBD Final Rule 

Table 16. Total Estimated OBD Costs per Engine for Over 14,000 Pound Applications 

(2007 dollars) 

Year CY 

Total $/engine 

Diesel Gasoline 

1 2006 $40 $50 

2 2007 $40 $49 

3 2008 $39 $48 

4 2009 $139 $71 

5 2010 $125 $77 

6 2011 $123 $76 

7 2012 $155 $75 

8 2013 $61 $70 

9 2014 $60 $70 

10 2015 $107 $70 

11 2016 $58 $68 

12 2017 $57 $67 

13 2018 $102 $67 

14 2019 $58 $68 

15 2020 $57 $67 

16 2021 $100 $67 

17 2022 $58 $68 

18 2023 $57 $67 

19 2024 $98 $67 

20 2025 $57 $68 

21 2026 $57 $67 

22 2027 $96 $67 

23 2028 $57 $67 

24 2029 $57 $67 

25 2030 $95 $67 

26 2031 $57 $67 

27 2032 $57 $67 

28 2033 $93 $67 

29 2034 $57 $67 

30 2035 $57 $67 

3.2 Cost Analysis for 8,500 to 14,000 Pound Diesel Applications 

We have used the same approach as described above for estimating costs associated with the 

8,500 to 14,000 pound OBD requirements. Since we have had OBD requirements for many 

years on such vehicles and engines the costs described here are incremental to past requirements. 

For hardware costs, we anticipate no new costs since all sensors and actuators should already be 

present and the computers should already be capable of handling the demands of OBD. We have 

estimated some new R&D costs for the DPF monitor since our current DPF monitoring 

requirement is to detect only a catastrophic failure while the final requirement would be more 

difficult. This requirement will begin in the 2010 model year and the R&D associated with it 

will be incurred over the years leading up to 2010. 

We have estimated that five manufacturers will be making diesels in the 8,500 to 14,000 

pound market. We have also used the same engineering and testing related costs for the under 

14,000 pound requirements as used above for the over 14,000 pound requirements. This is being 

conservative since most testing related costs, especially official emissions testing in a 

35 
Final Technical Support Document; HDOBD Final Rule 

certification test cell, is generally less costly on a chassis dynamometer than on an engine 

dynamometer. 

The analogous tables to those presented above are presented here. Table 17 shows the R&D 

costs for OBD algorithm development and application. We have estimated no costs for 

algorithm development since the same algorithm should suffice in both the over and under 

14,000 pound categories. We have estimated costs for algorithm application since the engines 

will be expected to operate slightly differently and, hence, we would expect some application 

costs to be incurred. We have estimated costs for one new threshold monitor for the new DPF 

monitoring requirement. As for the threshold monitor for NMHC catalyst monitoring, we 

believe that manufacturers will test out of this monitor and conduct a functional monitor instead. 

We have also estimated four and a half (on average) functional monitors associated with DPF 

and NMHC catalyst monitoring, and for nine continuity monitors associated with DPF and 

NMHC catalyst monitoring. We have also estimated costs for two engine families per 

manufacturer with two variants each. The total costs are estimated at $5.3 million to be spread 

over the four year period prior to the 2010 implementation date for the new monitoring 

requirements. 

36 
Final Technical Support Document; HDOBD Final Rule 

Table 17. R&D Costs for OBD Algorithm Development and Application – 

Diesel Applications Under 14,000 Pounds

(2007 dollars) 

A. Algorithm Development Costs weeks/monitor Cost/monitor # of monitors Total/Mfr Total

 System Threshold Monitors 

Engineer $ 

Technician $ 

Subtotal 

System Functional Monitors 

Engineer $ 

Technician $ 

Subtotal 

30 

15 

20 

5 

$69,000 

$21,000 

$90,000 

$46,000 

$7,000 

$53,000 

1 

5 

$90,000 

$239,000 

$450,000 

$1,195,000 

CCM Rationality Monitors 

Engineer $ 

Technician $ 

Subtotal 

CCM Continuity Monitors 

Engineer $ 

Technician $ 

Subtotal 

15 

1 

2 

0 

$34,000 

$1,000 

$35,000 

$5,000 

$0 

$5,000 

5 

9 

$158,000 

$45,000 

$790,000 

$225,000 

Total $532,000 $2,660,000 

B. Application Costs to each Family weeks/monitor Cost/monitor # of monitors Total/Family # families/mfr Total/Mfr Total

 System Threshold Monitors 

Engineer $ 

Technician $ 

Subtotal 

System Functional Monitors 

Engineer $ 

Technician $ 

Subtotal 

5 

10 

5 

10 

$11,000 

$14,000 

$25,000 

$11,000 

$14,000 

$25,000 

1 

5 

$25,000 

$113,000 

2 

2 

$50,000 

$226,000 

$250,000 

$1,130,000 

CCM Rationality Monitors 

Engineer $ 

Technician $ 

Subtotal 

Total 

3 

1 

$7,000 

$1,000 

$8,000 5 $36,000 

$174,000 

2 $72,000 

$348,000 

$360,000 

$1,740,000 

C. Application Costs to remaining Variants Total/Variant # variants/family # families/mfr Total/Mfr Total 

Total $44,000 2 2 $176,000 $880,000 

The R&D testing costs associated with the R&D effort that we have estimated are shown in 

Table 18. These costs are estimated at $860,000 to be spread over the four year period prior to 

the 2010 implementation date, and $260,000 to be spread over the four year period prior to the 

2013 implementation date, for the new monitoring requirements. 

37 
- - $0 

- - $0 - - $0 

- $0- $0

- - $0 

- - $0 

- - $0 

- - $0 

Final Technical Support Document; HDOBD Final Rule 

Table 18. OBD R&D Test Cell Costs – Diesel Applications Under 14,000 Pounds 

(2007 dollars) 

A. R&D Test Cell Costs - Diesel Cost for 2010 

Monitor Algorithms test wks # of monitors total test wks Costs/mfr # mfrs 

System monitor - threshold 3 5 

System monitor - functional 2 5 9.0 $63,000 5 Rationality monitor 1 5 4.5 $32,000 5 Subtotal $95,000 $ per year for 4 years $23,750 

System monitor - threshold 0.9 2.0 5 

System monitor - functional 0.6 5 2.0 5.4 $38,000 5 Rationality monitor 0.3 5 2.0 2.7 $19,000 5 Subtotal $57,000 $ per year for 4 years $14,250 

Monitor Application to each engine family 

factor 30% # of monitors # families/mfr total test wks Costs/mfr # mfrs 

Monitor Application to each engine family variant 

factor 10% # of monitors # families/mfr additional variants total test wks Costs/mfr # mfrs System monitor - threshold 0.3 2.0 1.0 5 

System monitor - functional 0.2 5 2.0 1.0 1.8 $13,000 5 Rationality monitor 0.1 5 2.0 1.0 0.9 $6,000 5 Subtotal $19,000 $ per year for 4 years $4,750 

Total R&D Test Cell Costs $171,000 

$ per year for 4 years $42,750 

B. R&D Test Cell Costs - Diesel Costs for 2013 

Monitor Algorithms test wks # of monitors total test wks Costs/mfr # mfrs 

System monitor - threshold 3 1 3.0 $21,000 5 System monitor - functional 2 0 5 Rationality monitor 1 0 5 Subtotal $21,000 $ per year for 4 years $5,250 

Monitor Application to each engine family 

factor 30% # of monitors # families/mfr total test wks Costs/mfr # mfrs System monitor - threshold 0.9 1 2.0 1.8 $13,000 5 System monitor - functional 0.6 2.0 5 

Rationality monitor 0.3 2.0 5 

Subtotal $13,000 $ per year for 4 years $3,250 

Monitor Application to each engine family variant 

factor 10% # of monitors # families/mfr additional variants total test wks Costs/mfr # mfrs System monitor - threshold 0.3 1 2.0 4.0 2.4 $17,000 5 System monitor - functional 0.2 2.0 4.0 5 

Rationality monitor 0.1 2.0 4.0 5 

Subtotal $17,000 $ per year for 4 years 

Total R&D Test Cell Costs $51,000 

$ per year for 4 years $12,750 

38 
Final Technical Support Document; HDOBD Final Rule 

For certification costs, we have first estimated costs for limit parts for certification 

demonstration at $5,500. We have estimated the costs of aging limit parts at $293,000 per parent 

engine using the same methodology as that described in section 3.1.2.b for aging of limit parts on 

engines meant for over 14,000 pound applications. Here we have used values appropriate to 

under 14,000 pound applications such as 110,000 mile useful life and weighted MPG of 14. 

Table 19 shows the estimated costs for demonstration testing. Note that we have not estimated 

costs for certification documentation since all 8,500 to 14,000 pound diesel applications are 

already generating and submitting OBD certification documentation. We have also estimated no 

costs for production evaluation testing since we do not have requirements for such testing in our 

under 14,000 pound OBD program. We have estimated costs for a total of 10 engine families 

with only one per manufacturer being demonstrated every three years, on average. The 30 year 

net present value costs for certification demonstration testing are estimated at $10 million and 

$6.2 million at a three percent and a seven percent discount rate, respectively. 

The total costs for the 8,500 to 14,000 pound diesel applications are shown in Table 20. The 

per vehicle numbers assume a two percent sales growth rate using an estimated sales number of 

470,000 in 2006; entries of $0 represent costs less than $1 per vehicle. The 30 year net present 

value of total costs are estimated at $16 million and $12 million at a three percent and a seven 

percent discount rate, respectively. Importantly, these costs represent the incremental costs of 

the additional OBD requirements, as compared to our current OBD requirements, for 8,500 to 

14,000 pound diesel applications and do not represent the total costs for OBD. 

39 
$0 $0 $0 $0 $0 

$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 

$0 $0 

$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 

$0 $0 

$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 

$0 $0 

$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 

$0 $0 

$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 

$0 $0 

$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 

$0 $0 

$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 

$0 $0 

$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 

$0 $0 

$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 

$0 $0 

$0 $0 $0 $0 $0 $0 $0 $0 $0 $0 

$0 $0 $0 $0 

Final Technical Support Document; HDOBD Final Rule 

Table 19. OBD Certification and Production Evaluation Testing Costs – Diesel Applications Under 14,000 P

(2007 dollars) 

Certification Demonstration Testing Related Production Evaluation Testing Related 

Year CY 

# of parent test 

engines 

Costs for Limit 

Parts 

DDV Testing 

Costs 

Total DDV 

Costs 

PE Testing - Scan Tool PE Testing - Monitors PE Testing - Ratios 

# of engine 

families for 

testing PE Costs 

# of OBD 

Groups tested 

PE Costs 

(incl vehicle 

rental) 

# of monitoring 

groups tested PE Co

1 2006 0 0 0 0 2 2007 0 0 0 0 3 2008 0 0 0 0 4 2009 5 $1,493,000 $277,000 $1,770,000 0 0 0 5 2010 0 0 0 0 6 2011 0 0 0 0 7 2012 5 $1,493,000 $277,000 $1,770,000 0 0 0 8 2013 0 0 0 0 9 2014 0 0 0 0 

10 2015 5 $1,493,000 $277,000 $1,770,000 0 0 0 11 2016 0 0 0 0 12 2017 0 0 0 0 

13 2018 5 $1,493,000 $277,000 $1,770,000 0 0 0 14 2019 0 0 0 0 15 2020 0 0 0 0 16 2021 5 $1,493,000 $277,000 $1,770,000 0 0 0 17 2022 0 0 0 0 18 2023 0 0 0 0 19 2024 5 $1,493,000 $277,000 $1,770,000 0 0 0 20 2025 0 0 0 0 21 2026 0 0 0 0 22 2027 5 $1,493,000 $277,000 $1,770,000 0 0 0 23 2028 0 0 0 0 24 2029 0 0 0 0 25 2030 5 $1,493,000 $277,000 $1,770,000 0 0 0 

26 2031 0 0 0 0 27 2032 0 0 0 0 28 2033 5 $1,493,000 $277,000 $1,770,000 0 0 0 29 2034 0 0 0 0 30 2035 0 0 0 0 

NPV @ 3% $8,595,000 $1,595,000 $10,189,000 NPV @ 7% $5,202,000 $965,000 $6,168,000 

40 
$0 $0

$0 $0

$0 $0

$0

$0 $0

$0 $0

$0

$0 $0 $0 $0

$0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0

$0 $0

$0 $0 $0 $0

$0 $0 $0 $0

Final Technical Support Document; HDOBD Final Rule 

Table 20. Total Estimated OBD Costs – Diesel Applications Under 14,000 Pounds 

(2007 dollars) 

Year CY R&D Cert/PE Testing Hardware Total 

Projected 

Sales $/vehicle 

1 2006 $1,533,750 $1,533,750 470,000 $3 

2 2007 $1,533,750 $1,533,750 479,400 $3 

3 2008 $1,533,750 $1,533,750 488,800 $3 

4 2009 $1,597,500 $1,770,000 $3,367,500 498,200 $7 

5 2010 $63,750 $63,750 507,600 $0 

6 2011 $63,750 $63,750 517,000 $0 

7 2012 $63,750 $1,770,000 $1,833,750 526,400 $3 

8 2013 535,800 $0 

9 2014 545,200 $0 

10 2015 $1,770,000 $1,770,000 554,600 $3 

11 2016 564,000 $0 

12 2017 573,400 $0 

13 2018 $1,770,000 $1,770,000 582,800 $3 

14 2019 592,200 $0 

15 2020 601,600 $0 

16 2021 $1,770,000 $1,770,000 611,000 $3 

17 2022 620,400 $0 

18 2023 629,800 $0 

19 2024 $1,770,000 $1,770,000 639,200 $3 

20 2025 648,600 $0 

21 2026 658,000 $0 

22 2027 $1,770,000 $1,770,000 667,400 $3 

23 2028 676,800 $0 

24 2029 686,200 $0 

25 2030 $1,770,000 $1,770,000 695,600 $3 

26 2031 705,000 $0 

27 2032 714,400 $0 

28 2033 $1,770,000 $1,770,000 723,800 $2 

29 2034 733,200 $0 

30 2035 742,600 $0 

NPV @ 3% $5,918,000 $10,189,000 $0 $16,107,000 

NPV @ 7% $5,371,000 $6,168,000 $0 $11,539,000 

3.3 Updated 2007/2010 HD Highway Costs Including OBD 

Table 21 shows the cost estimates for the 2007/2010 heavy-duty highway program. As 

shown, the 30 year net present value cost at a three percent discount rate was estimated at $70 

billion with $25 billion of that being engine related costs (these costs are in terms of 1999 

dollars). 

41 
Final Technical Support Document; HDOBD Final Rule 

Table 21. Costs of the 2007/2010 Heavy-duty Highway Program 

(All Costs in $Millions; 1999 Dollars) 

Year 

Calendar 

Year 

Diesel Engines 

HD2007 FRM 

Gasoline 

Vehicles & 

Engines HD2007 

FRM Diesel Fuel 

Total Costs -

Engines, Fuel 

1 2006 -$80 $0 $880 $799 

2 2007 $1,266 $0 $1,786 $3,052 

3 2008 $1,321 $46 $1,809 $3,177 

4 2009 $1,072 $80 $1,904 $3,056 

5 2010 $1,520 $81 $2,014 $3,615 

6 2011 $1,225 $82 $2,128 $3,434 

7 2012 $1,133 $83 $2,160 $3,376 

8 2013 $1,157 $78 $2,192 $3,427 

9 2014 $1,180 $79 $2,225 $3,484 

10 2015 $1,141 $80 $2,258 $3,480 

11 2016 $1,156 $82 $2,292 $3,530 

12 2017 $1,159 $83 $2,327 $3,568 

13 2018 $1,182 $84 $2,362 $3,628 

14 2019 $1,205 $85 $2,397 $3,687 

15 2020 $1,226 $86 $2,433 $3,746 

16 2021 $1,247 $87 $2,469 $3,804 

17 2022 $1,268 $89 $2,506 $3,863 

18 2023 $1,288 $90 $2,544 $3,921 

19 2024 $1,307 $91 $2,582 $3,980 

20 2025 $1,326 $92 $2,621 $4,039 

21 2026 $1,344 $93 $2,660 $4,098 

22 2027 $1,362 $94 $2,700 $4,157 

23 2028 $1,380 $95 $2,741 $4,217 

24 2029 $1,398 $97 $2,782 $4,276 

25 2030 $1,415 $98 $2,824 $4,337 

26 2031 $1,432 $99 $2,866 $4,397 

27 2032 $1,450 $100 $2,909 $4,459 

28 2033 $1,467 $101 $2,953 $4,521 

29 2034 $1,484 $102 $2,997 $4,583 

30 2035 $1,500 $104 $3,042 $4,646 

NPV @ 3% $23,721 $1,514 $45,191 $70,427

NPV @ 7% $14,369 $877 $26,957 $42,203

Source: EPA420-R-00-026; Table V.D-1 & Appendix VI-B; December 2000. 

The updated 2007/2010 program costs are shown in Table 22, which now include the new 

OBD-related costs. The 2007/2010 program costs of $88 billion (2007 dollars) far outweigh the 

OBD related costs of $1.2 billion. Note that the 2007/2010 program costs of $70 billion were 

generated using 1999 dollars which, in 2007 dollars, is just under $88 billion. We have adjusted 

the 1999 dollars to 2007 dollars using the Consumer Price Index. The CPI data are shown in 

Table 23. 

42 
Final Technical Support Document; HDOBD Final Rule 

Table 22. Updated 2007/2010 Program Costs Including New OBD-Related Costs 

(All costs in $Millions; 2007 dollars) 

Gasoline 

Vehicles & Gasoline Diesel Total Costs -

Calendar Engines Engines >14K Applications Engines, OBD, 

Year 

Diesel Engines Diesel Engines 

Year HD2007 FRM >14K OBD HD2007 FRM OBD 8500-14K OBD Diesel Fuel Fuel 

1 2006 -$100 $26 $0 $2 $2 $1,095 $1,025 

2 2007 $1,576 $26 $0 $2 $2 $2,223 $3,828 

3 2008 $1,644 $26 $57 $2 $2 $2,251 $3,982 

4 2009 $1,334 $94 $100 $3 $3 $2,370 $3,904 

5 2010 $1,892 $71 $101 $2 $0 $2,507 $4,573 

6 2011 $1,525 $71 $102 $2 $0 $2,648 $4,349 

7 2012 $1,410 $95 $103 $2 $2 $2,688 $4,301 

8 2013 $1,440 $44 $97 $3 $0 $2,728 $4,312 

9 2014 $1,469 $44 $98 $3 $0 $2,769 $4,384 

10 2015 $1,420 $81 $100 $3 $2 $2,810 $4,416 

11 2016 $1,439 $44 $102 $3 $0 $2,853 $4,440 

12 2017 $1,442 $44 $103 $3 $0 $2,896 $4,489 

13 2018 $1,471 $80 $105 $3 $2 $2,940 $4,601 

14 2019 $1,500 $46 $106 $3 $0 $2,983 $4,638 

15 2020 $1,526 $46 $107 $3 $0 $3,028 $4,710 

16 2021 $1,552 $82 $108 $4 $2 $3,073 $4,821 

17 2022 $1,578 $48 $111 $4 $0 $3,119 $4,859 

18 2023 $1,603 $48 $112 $4 $0 $3,166 $4,933 

19 2024 $1,627 $84 $113 $4 $2 $3,213 $5,043 

20 2025 $1,650 $50 $114 $4 $0 $3,262 $5,081 

21 2026 $1,673 $50 $116 $4 $0 $3,311 $5,153 

22 2027 $1,695 $87 $117 $4 $2 $3,360 $5,264 

23 2028 $1,717 $52 $118 $4 $0 $3,411 $5,303 

24 2029 $1,740 $52 $121 $4 $0 $3,462 $5,379 

25 2030 $1,761 $89 $122 $4 $2 $3,515 $5,492 

26 2031 $1,782 $54 $123 $4 $0 $3,567 $5,531 

27 2032 $1,805 $55 $124 $4 $0 $3,620 $5,608 

28 2033 $1,826 $91 $126 $4 $2 $3,675 $5,723 

29 2034 $1,847 $56 $127 $4 $0 $3,730 $5,764 

30 2035 $1,867 $57 $129 $4 $0 $3,786 $5,843 

NPV @ 3% $29,522 $1,149 $1,884 $63 $16 $56,243 $88,876

NPV @ 7% $17,882 $706 $1,091 $37 $12 $33,550 $53,279

43 
Final Technical Support Document; HDOBD Final Rule 

Table 23. Consumer Price Index Data 

Series Id:    CUUR0000SA0,CUUS0000SA0 Not Seasonally Adjusted Area:  U.S. city average Item:  All items Base Period:  1982-84=100 

Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 

1998 161.6 161.9 162.2 162.5 162.8 163 163.2 163.4 163.6 164 164 163.1999 164.3 164.5 165 166.2 166.2 166.2 166.7 167.1 167.9 168.2 168.3 168.2000 168.8 169.8 171.2 171.3 171.5 172.4 172.8 172.8 173.7 174 174.1 172001 175.1 175.8 176.2 176.9 177.7 178 177.5 177.5 178.3 177.7 177.4 176.2002 177.1 177.8 178.8 179.8 179.8 179.9 180.1 180.7 181 181.3 181.3 180.2003 181.7 183.1 184.2 183.8 183.5 183.7 183.9 184.6 185.2 185 184.5 184.2004 185.2 186.2 187.4 188 189.1 189.7 189.4 189.5 189.9 190.9 191 190.2005 190.7 191.8 193.3 194.6 194.4 194.5 195.4 196.4 198.8 199.2 197.6 196.2006 198.3 198.7 199.8 201.5 202.5 202.9 203.5 203.9 202.9 201.8 201.5 201.2007 202.416 203.499 205.352 206.686 207.949 208.352 208.299 207.917 208.49 208.936 210.177 210.03

Source: www.bls.gov/cpi. 

44 
Final Technical Support Document; HDOBD Final Rule 

References 

1

 Docket ID Number EPA-HQ-OAR-2005-0047 which can be found at www.regulations.gov. 2

 Kato, N.; Hamada, Y.; Kurachi, H. Performance of Thick Film NOx sensor on Diesel and 

Gasoline Engines. Soc. Automot. Eng. Tech. Pap. Ser. 1997, No. 970858.

3

 Schar, C.; Onder, C.; Geering, H. Control of a Urea SCR Catalytic Converter System for a 

Mobile Heavy Duty Diesel Engine. Soc. Automot. Eng. Tech. Pap. Ser. 2003, No. 2003-01-0776.

4

 Kato, N.; Kokune, N.; Lemire, B.; Walde, T. Long Term Stable NOx Sensor with Integrated InConnector Control Electronics. Soc. Automot. Eng. Tech. Pap. Ser. 1999, No. 1999-01-0202.

5

 Orban, J.; Naber, S.; Sharp, C.; Khair, M.; McGill, R. Long-Term Aging of NOx Sensors in 

Heavy-Duty Engine Exhaust. SAE Tech. Pap. Ser. 2005, No. 2005-01-3793.

6

 Orban, J.; Naber, S.; Sharp, C.; Khair, M.; McGill, R. Long-Term Aging of NOx Sensors in 

Heavy-Duty Engine Exhaust. SAE Tech. Pap. Ser. 2005, No. 2005-01-3793.

7

 Schenk, C.; McDonald, J.; Laroo, C. High-Efficiency NOx and PM Exhaust Emission Control 

for Heavy-Duty On-Highway Diesel Engines – Part Two. SAE Tech. Pap. Ser. 2001, No. 2001­

01-3619. 

8

 May, M.; Adelman, B. APBF-DEC Heavy Duty NOx Adsorber/DPF Project: Heavy-Duty 

Linehaul Platform Final Project Meeting. Presented at the Heavy-Duty Final Project Meeting, 

Rosemont, IL, April 27, 2004. 

9

 66 FR 5002 and 69 FR 38958, respectively.

10 Board approved as of July 21, 2005 (see 13 CCR 1971.1).

11 “Final Regulatory Analysis: Control of Emissions from Nonroad Diesel Engines,” EPA420-R04-007, May 2004. 

45