From: Moulis, Charles

Sent: Thursday, January 23, 2014 5:49 PM

To: Jed R. Mandel , EMA ; John C abaniss

, G lobal A utomakers ; Gi edri u s

A mbrozaitis

, Alliance of Automobile Manufacturers
Subject: Potential Revisions for DEF Replenishment Regulations

Attachments: Review Draft SCR Regs 012314.docx

As you know, EPA proposed last year to codify the DEF refill policy it has been applying to SCR

equipped highway and nonroad engines through the (b)(7) process. That (b)(7) policy allowed
manufacturers to specify DEF refill without meeting the minimum mai ntenance intervals that would otherwise apply for catalyst maintenance, provided they incorporated features (including performance inducements) to ensure that engines do not operate without DEF.

In response to comments, we are now considering shorter refi ll intervals than were proposed in the NPRM (and thus shorter than were allowed under the (b)(7) process). As part of our
consideration of these shorter intervals, we are also considering other changes to the proposed
regulatory text. In particular, we a re considering the following clarifications:

1. Clarifying that intervals for chassis

- certified vehicles may be calculated based on typical
operation, while for engines they must be based on worst case operation.

2. Clarifying that certain demonstrations identi fied in §86.004

- 25(b)(6)(ii), §86.1834

- 01(b)(6)(ii), and §1039.125(a)(1) are not sufficient to demonstrate that DEF
replenishment will occur.

3. Clarifying that any size DEF tank may be used for laboratory engine testing.

While these specific provisions were not explicitly discussed in the NPRM, they reflect the
broader principle that was discussed

– that the rulemaking is generally codifying the existing
approach to addressing DEF refills. Since these clarifications merely reflect what has applied

under the (b)(7) process, we believe they represent a logical outgrowth of the NPRM.
Nevertheless, we believe it is appropriate to provide affected parties the opportunity to
comment on the regulatory text we are considering, which is attached.

Since we share the manufacturers’ interest in completing this rule very soon, we are asking that
you let us know by January 30th if you have comments on these possible clarifications, which
are highlighted in the attached regulatory text. Please note that we are not asking for
additional comments on the intervals themselves beyond what manufacturers already provided
during the official comment period.

I look forward to hearing from you.HEAVY

- DUTY

§ 86.004

- 25 Maintenance.

* * * * * (b) * * * (4) For diesel

- cycle heavy

- duty engines, emission

- related maintenance in addition to or at shorter intervals than the following specified values will not be accepted as technologically

necessary, except as provided in paragraph (b)(7) of this section:

* * * * * (v) For engines that use selective catalytic reduction, the diesel exhaust fluid (DEF) tank must be sized so that the replenishment of diesel exhaust fluid can occur at an interval, in miles or hours of vehicle operation, that is no less than the miles or hours of vehicle operation corresponding to the vehicle’s fuel capacity. Use good engineering judgment to ensure that you meet this requirement for worst case operation. For example, if yo ur highest rate of DEF consumption (relative to fuel consumption) will occur under highway driving conditions, the DEF tank should

be la rge enough that a single tank of DEF would be enough to continue proper operation of the SCR system for whatever number of highway miles is possible with a single tank of fuel. For laboratory engine testing, any size DEF tank and/or fuel tank may be used. For our testing of engines, we may require you to provide us with a production type DEF tank, including any

associated sensors.

* * * * * (6)(i) The following components are defined as critical emission

- related components:

* * * * * (H) Components comprising the selective catalytic reduction system (including diesel exhaust fluid tank). (I) Any other component whose primar y purpose is to reduce emissions or whose failure would commonly increase emissions of any regulated pollutant without significantly degrading engine performance.

* * * * * (ii) All critical emission

- related scheduled maintenance must have a reasonable l ikelihood of being performed in

- use. The manufacturer shall be required to show the reasonable likelihood of such maintenance being performed in

- use, and such showing shall be made prior to the performance of the maintenance on the durability data vehicle. Critical emission

- related

scheduled maintenance items which satisfy one of the conditions defined in paragraphs (b)(6)(ii) (A)

- (F) of this section will be accepted as having a reasonable likelihood of the maintenance item being performed in

- use
, except th at for DEF replenishment, the manufacturer must satisfy paragraph (b)(6)(ii)(A) or (F) for us to accept that there is a reasonable likelihood of the maintenance item being performed in

- use.

* * * * *LIGHT

- DUTY

§ 86.1834

- 01 Allowable maintenance.

* * * * * (b) * * * (4) For diesel

- cycle vehicles, emission

- related maintenance in addition to, or at shorter intervals than the following will not be accepted as technologically necessary, except as provided in paragraph (b)(7) of this section:

* * * * * (iii) For vehicles that use selective catalytic reduction, the replenishment of diesel exhaust fluid shall occur at an interval that is no less than 4,000 miles for typical operation

. * * * * * (6) * * * (i) * * * (H) Components comprising the selective catalytic reduction system (including diesel exhaust fluid tank). (I) Any other component whose primary purpose is to reduce emissions or whose failure would commonly increase emissions of any regulated pollutant without significantly degrading engine perf ormance.

* * * * * (ii) All critical emission

- related scheduled maintenance must have a reasonable likelihood of being performed in use. The manufacturer shall be required to show the reasonable likelihood of such maintenance being performed in use, and su ch showing shall be made prior to the performance of the maintenance on the durability data vehicle. Critical emission

- related

scheduled maintenance items which satisfy one of the conditions defined in paragraphs (b)(6)(ii) (A)

- (F) of this section will be accepted as having a reasonable likelihood of the maintenance item being performed in

- use
, except that for DEF replenishment, the manufacturer must satisfy paragraph (b)(6)(ii)(A) or (F) of this section for us to accept that there is a reasonable likelihoo d of the maintenance item being performed in

- use.NONROAD

§ 1039.125 What maintenance instructions must I give to buyers?

* * * * * (a) * * *

(1) You demonstrate that the maintenance is reasonably likely to be done at the recommended

intervals on in

- use engines. We will accept scheduled maintenance as reasonably likely to occur if you satisfy any of the following conditions

, with the exception that paragraph s (a)(1)(ii) and (iii) of this section do not apply for DEF replenishment :

* * * * * (2) * * * (iii) For SCR systems, the minimum interval for replenishing the diesel exhaust fluid is the number of engine operating hours necessary to consume a full tank of fuel starting from full fuel capacity for the equipment. Use good engineering judgment t o ensure that you meet this requirement for worst case operation. For laboratory engine testing, any size DEF tank and/or fuel tank may be used. For our testing of engines, we may require you to provide us with a production type DEF tank, including any a ssociated sensors. (3) * * * (iii) For SCR systems, the minimum interval for replenishing the diesel exhaust fluid is the number of engine operating hours necessary to consume a full tank of fuel starting from full fuel capacity for the equipment. Use good engineering judgment to ensure that you meet this requirement for worst case operation. For laboratory engine testing, any size DEF tank and/or fuel tank may be used. For our testing of engines, we may require you to provide us with a production typ e DEF tank, including any associated sensors.

* * * * *