Hogan Lovells US LLP

Columbia Square

555 Thirteenth Street, NW

Washington, DC 20004

T +1 202 637 5600

F +1 202 637 5910

www.hoganlovells.com

September 27, 2011

Karl Simon, Director

Compliance and Innovative Strategies Division

Office of Transportation and Air Quality

United States Environmental Protection Agency

1200 Pennsylvania Avenue NW

Washington, DC 20460

Re: Request for Updated Scheduled Maintenance Intervals for Selective Catalytic

Reduction Technologies for Model Years 2012 and Later

Dear Mr. Simon:

In their petition dated August 18, 2011, Chrysler Group, LLC, Cummins Inc., Detroit Diesel

Corp., Daimler Trucks North America LLC, Ford Motor Company, Mack Trucks Inc., PACCAR Inc.,

UD Trucks Corporation, and Volvo Group North America, LLC, (collectively the “SCR Engine

Manufacturers”) requested revised scheduled maintenance intervals for selective catalytic reduction

(“SCR”) technologies for model years 2012 and later pursuant to 40 C.F.R. § 86.094-25(b)(7)(ii).

This letter provides additional information and data in support of that petition.

I. Space and Weight Constraints

In EPA’s November 9, 2009 Approval of New Scheduled Maintenance for Selective Catalyst

Reduction Technologies (the “2009 Notice”), EPA made two related findings of fact with respect to

size and weight constraints. First, EPA concluded that diesel exhaust fluid (“DEF”) tank sizes were

limited by weight and space constraints, and that tanks larger than those recommended by

manufacturers were not reasonably feasible. EPA explained that “longer intervals than those

requested by the manufacturers would require DEF tanks that are too large or too heavy to be

feasibly incorporated into vehicles. . . . Because of inherent space and weight constraints in the

configuration and efficient operation of heavy-duty vehicles, there are size limits on the DEF tanks.”1

EPA explained that:

The extra weight associated with the DEF required to meet the 2:1 or 3:1 refill

intervals . . . represents a significant challenge to manufacturers seeking to meet

both weight and size requirements for their vehicle designs. EPA believes that in

1 Control of Emissions from New Highway Vehicles and Engines: Approval of New Scheduled

Maintenance for Selective Catalyst Reduction Technologies, 74 Fed. Reg. 57,671, 57,673 (Nov. 9, 2009).
- 2 -

light of the existing tight space constraints and the overall desire to maximize cargocarrying capacity to minimize emissions and meet consumer operational demands,

and the built-in DEF tank size buffer to insure DEF refills, that the DEF tank sizes

associated with the 2:1 and 3:1 refill intervals are technologically necessary. EPA

believes that requiring tank sizes above these ratios will cause increases in space

constraints and weight that would not be appropriate for these vehicles.

. . . EPA believes that longer refill intervals than those noted above would require

larger and heavier DEF tanks, and the design and engineering work performed by

manufacturers thus far indicate that the recommended DEF refill intervals noted

above approximate the maximum feasible maintenance intervals associated with

reasonable DEF tank sizes.2

There has been no increase in the space available for DEF tanks since 2009, therefore

EPA’s 2009 analysis and conclusions about the “tight space constraints” and maximum reasonable

tank size remain accurate and valid.3 What has changed dramatically is the level of DEF dosing,

and the need to carry more DEF to meet a given DEF tank size ratio, like the 2:1 ratio. EPA’s new

fuel economy standards for heavy-duty on-highway trucks4and similar voluntary efficiency

improvement measures will significantly increase the space and weight demands associated with

DEF storage, unless the proposed 1:1 ratio requirement is adopted. In other words, if EPA does not

approve the use of 1:1 tank size ratios, it would effectively be requiring 2:1 tanks that are

significantly larger than the tank sizes that EPA previously concluded were the “maximum

feasible . . . associated with reasonable DEF tank sizes.”5

Specifically, SCR engine manufacturers are planning to use increased DEF dosing rates to

meet both near and longer-term fuel economy and GHG reduction targets. The level of increased

dosing needed to enable meeting those requirements is significant in many cases. DEF dosing

rates vary by manufacturer, vehicle application, and in-use operating conditions, but the near-term

increases are generally expected to be in the range of 25-50%. To meet the next round of GHG

reduction requirements, some manufacturers expect to increase DEF dosing by as much as 100%

over current levels. These increased levels of dosing will require a corresponding increase in DEF

tank capacity and size to meet the existing 2:1 tank ratio requirements. For example, increasing

DEF dosing by 40% on average would require an increase in DEF tank size of approximately 40%

(depending on how much extra capacity was included in the tanks used in previous model years).

The shape, size and location of DEF tanks on a truck frame are constrained by a number of factors

including: the need to place the tank below the filler-neck; the need for clearance from other

components such as fuel tanks, battery boxes, air tanks, diesel particulate filters, and the drive axle

and wheels; the need for gravity feed; body installation requirements; clear-back-of-cab

requirements; weight distribution requirements; bridge formula and related axle placement issues;

2

Id. at 57,674.

3

See id.

4 Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty

Engines and Vehicles, 76 Fed. Reg. 57,106 (Sept. 15, 2011).

5

74 Fed. Reg. at 57,674.
- 3 -

and fuel capacity/driving range demands.

The graphics attached at Appendix A depict the position and relationship between these

components and the resulting space constraints associated with increasing DEF tank sizes on

several Volvo applications. These graphics demonstrate that the tank sizes approved in 2009 were

the largest feasible for those MY 2010 applications. As noted, there have been no changes to these

trucks which would increase the amount of space available for larger DEF tanks. For numerous

PACCAR trucks, the near-term tank size increase under a 2:1 rule would require an additional 10

inches of longitudinal frame rail space if the 1:1 ratio is not applied more broadly. Appendix B

depicts several examples of PACCAR applications where increased DEF tank sizes for MY 2013

trucks would require significant vehicle re-engineering of the chassis and drive train, as well as the

DEF storage system (including revalidation of the DEF thaw characteristics). On some truck

applications the use of a larger tank would simply be impossible without a major re-design of the

vehicle. On other applications, the use of a larger tank could be possible in theory, but would involve

creating a custom designed tank shape for the specific application, which would be both extremely

time-consuming and cost-prohibitive.

In addition to the space constraints, forcing larger DEF tanks through a 2:1 tank requirement

would also increase vehicle weight in a way that is directly contrary to the objectives of EPA’s recent

GHG rulemaking. SCR Engine Manufacturers have looked at the weight impact. In some cases, the

larger capacity would be achieved by utilizing larger DEF tanks from the existing range of tank

options; in other cases, custom tanks would be required. The increase in weight associated with

failure to adopt the proposed 1:1 requirement would be in the range of 100 - 110 pounds for MY

2013, assuming that the next larger existing tank size could be employed. EPA recognized that

reductions in vehicle weight of as little as 80 pounds were relevant to its GHG reduction goals.6

II. Lead Time and Stability

Now is the appropriate time to grant the SCR Engine Manufacturers’ (b)(7) petition for all of

the reasons discussed in the August 18th petition, including increased availability of DEF, significant

changes in inducement strategies, and current and anticipated changes in vehicle designs. Delaying

approval of reduced maintenance intervals for MY 2013 will prevent manufacturers from

implementing engine and vehicle plans developed pursuant to EPA’s new GHG rule and will

significantly undermine those regulations. Without approval of the 1:1 tank ratio for MY 2013,

manufacturers will not be able to utilize the transitional flexibilities built into the regulations, which are

designed to facilitate compliance with the new GHG regulations.

One of these important GHG provisions offers the ability to begin generating CO2 emissions

credits with engines certified in MY 2013 pursuant to 40 C.F.R. § 1036.150(a). SCR Engine

Manufacturers are planning to begin generating these credits with MY 2013 engines. Generating

these credits in many cases will require the near-term levels of increased DEF dosing, and

6 Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty

Engines and Vehicles, 75 Fed. Reg. 74,152, 74,216-17 (proposed Nov. 30, 2010).
- 4 -

corresponding tank size increases, referenced above. In addition, a number of manufacturers will

seek to use the optional compliance flexibilities associated with meeting the new CO2 standards in

MY 2013, such as the alternative phase-in standards of 40 C.F.R. § 1036.150(e). MY 2013 engine

production can begin as early as January 2, 2012. Accordingly, it is critical that the requested use of

1:1 tank ratios be approved by EPA in the context of renewing EPA’s existing (b)(7) approval, which

is only applicable through MY 2011. Failure to approve this request at the same time EPA issues its

(b)(7) decision for model year 2012 would essentially eliminate the production and compliance

planning lead time necessary for manufacturers to utilize the MY 2013 GHG flexibility provisions of

the final GHG rule.

The need to incorporate onboard diagnostic (OBD) capability in MY 2013 provides an

additional and independent basis for granting the 1:1 (b)(7) petition by the end of the current

calendar year. Specifically, EPA’s OBD regulations for heavy-duty diesel engines will fully phase-in

in MY 2013. OBD monitoring strategies must take into account engine control strategies that affect

both criteria pollutant emissions and CO2. If manufacturers are not able to incorporate enhanced

CO2 performance in MY 2013 with increased DEF dosing, they would be forced to incorporate one

OBD monitoring strategy for a single model year (MY 2013), and then replace it with a new OBD

strategy in MY 2014 when the CO2 regulations become mandatory. In other words, if manufacturers

cannot improve CO2 performance for MY 2013 as desired, they would only have a single year of

regulatory stability for the OBD systems that must be incorporated in MY 2013.

EPA has consistently recognized the need for adequate lead time and stability in connection

with the engineering and product development necessary for manufacturers to meet emissionsrelated maintenance requirements. Consistent with the stability provisions of section 202 of the

Clean Air Act for emissions standards, EPA’s 2009 (b)(7) notice established a DEF refill interval that

would remain in effect for three years, even though the EPA recognized that DEF availability was still

evolving at that time.7 As discussed in the August 18th petition, the developments since 2009

support an approval for reduced SCR maintenance intervals that would remain effective indefinitely

(until such time as compelling evidence may indicate that the DEF replenishment interval should be

revisited). A longer approval time period would provide greater certainty for manufacturers for

planning and design purposes, thereby reducing costs and enabling manufacturers to focus on other

design developments such as GHG reductions, and it would reduce the administrative burden on the

agency.

EPA should make every effort to provide maximum lead time and stability with respect to

required maintenance intervals under (b)(7). Similarly, EPA should make every effort to ensure that

the requirements it establishes under (b)(7) do not defeat the regulatory compliance options

established by its recent GHG rulemaking. For all of the foregoing reasons, EPA should approve the

SCR Engine Manufacturers’ petition with respect to DEF tank sizes as soon as possible.

* * *

7

74 Fed. Reg. at 57,674.
- 5 -

We look forward to your response to this request. Please contact us if we can provide any

additional information.

Sincerely,

R. Latane Montague

Partner

latane.montague@hoganlovells.com

D 202.637.6567
APPENDIX A








APPENDIX B
General Freight/Household Goods

Would require increasing

wheelbase by 10 inches

240 gallons fuel

- Current: medium DEF tank

- Without requested 1:1 ratio:

large DEF tank
Refrigerated Freight/Produce Tractor

Would require

increasing wheelbase

by 10 inches

150 gallons fuel

- Current: small DEF tank

- Without requested 1:1 ratio:

medium DEF tank
150 gallons fuel

- Current: small DEF tank

- Without requested 1:1 ratio:

medium DEF tank

Construction Block/Crane

Customer requires clear back of cab

for body installation and cannot

extend the wheelbase
Wrecker Body Truck

Customer requires clear back of cab

for body installation and cannot

extend the wheelbase

150 gallons fuel

- Current: small DEF tank

- Without requested 1:1 ratio:

medium DEF tank
Winch Tractor

Would require increasing

wheelbase by 10 inches

225 gallons fuel

- Current: medium DEF tank

- Without requested 1:1 ratio:

large DEF tank
4-Axle Truck

225 gallons fuel

- Current: medium DEF tank

- Without requested 1:1 ratio:

large DEF tank

Would require increasing

wheelbase by 10 inches