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GHG Phase 2 Rules Don't Pass OEM Muster... Yet

OEM comments on proposed EPA/NHTSA Phase 2 GHG regs show they’re nowhere near ready for prime time. What the agencies say in reply will speak volumes on where the rule is headed.

Jim Park
Jim ParkFormer HDT Equipment Editor
Read Jim's Posts
November 13, 2015
GHG Phase 2 Rules Don't Pass OEM Muster... Yet

OEM comments on proposed EPA/NHTSA Phase 2 GHG regs show they’re nowhere
near ready for prime time. What the agencies say in reply will speak volumes on where the rule is headed.

6 min to read


OEM comments on proposed EPA/NHTSA Phase 2 GHG regs show they’re nowhere near ready for prime time. What the agencies say in reply will speak volumes on where the rule is headed.

If the proposed Phase 2 greenhouse gas/fuel efficiency regulations for trucks go into effect as currently written, they may stretch North American truck and engine makers to the length and breadth of their capability.

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Although publicly the companies may disagree with that statement, that’s our take after reading the OEM comments filed in response to the proposed rule.

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Reading between the lines of the 400-plus pages of comments, you can sense the OEMs’ frustration and anxiety over what might be coming our way in a very short period of time.

For example, as Martin Daum, president and CEO of Daimler Trucks North America, told reporters at the recent American Trucking Associations management conference, “I’m really confident we can reach it, but I don’t know how,” pointing out that DTNA is budgeting a record $653 million for research and development next year.

The broad outline

“Greenhouse Gas Emission Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles, Phase 2,” is still just a proposed rule, issued jointly by the Environmental Protection Agency and the National Highway Traffic Safety Administration. It’s scheduled to become final, at President Obama’s request, by March 2016. That leaves the two agencies a scant six months to review the comments and make or deny the requested changes. In their comments, the OEMs stress that most of the requested changes are not optional. 

All six North American truck and engine makers filed comments on the proposed rule: Caterpillar, Cummins, Daimler, Navistar, Paccar, and the Volvo Group. All except Cummins also filed a joint comment submission that outlines the concerns held by the group as a whole, many of which were also included in their individual submissions.

The 10-page joint submission outlines seven basic principles the group says must be addressed before the regulation can be finalized:

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  • Regulation must appropriately reflect real-world reductions;

  • There must be a single, national GHG regulation adopted by EPA, NHTSA and the California Air Resources Board;

  • Expected technologies must be appropriately demonstrated;

  • Expected technology penetration rates must align with market needs and legal restrictions;

  • Regulation must take into account total cost of ownership;

  • Protocols must be clearly defined, and accommodate production and test variability; and

  • Regulation must recognize the trade-off of NOx and CO2 reduction targets.

Individually, each OEM expressed conceptual support of the rule and pledged to work closely with EPA and NHTSA to bring it to fruition. They also outlined areas they believe are flawed, not feasible, or plain impossible without significant changes.   

One of the major concerns is the compressed timeline for finalization of the rule. The Volvo Group, for example, noted that “major parts of the proposal are incomplete, undecided, or subject to ongoing changes such that it is impossible to make any reasonable assessment of the true stringency of the proposal or the relative merits of various technology packages to meet the proposed targets.”

In other words, stakeholders cannot make accurate predictions or base any assumptions on moving targets. With more than 400 pages of comments from the OEMs alone and untold thousands of others from other concerned parties, there are bound to be changes that will have to be analyzed before any determinations can be made. That, the OEMs say, will take time. They are urging the agencies to take their time, even if it runs up against the politically driven deadlines. 

“To participate meaningfully, interested parties must have a complete and settled picture of what the agency is proposing,” the Volvo Group said in its comments. “In light of the substantial elements of the proposal that remain either incomplete, unsettled or both, it simply cannot be said that the Volvo Group and other interested parties have had a reasonable opportunity to provide fully informed input into the rulemaking process.”

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The OEMs also are calling for reasonable lead time for various mandates to promote stability. In particular, one OEM notes, Alternative 4 (basically, pulling the 2027 proposed standards ahead to 2024) is too stringent, and accelerating an already very stringent proposal is unworkable. 

Specific concerns

At least one OEM expressed concern about future powertrain modifications. Once any element of the powertrain is included in the initial certification, they may be “frozen” and unable to be changed, it said. Currently, engine re-rating is a routine practice when a different engine horsepower is required by a second or third owner of a vehicle or the first owner if working conditions change.

Al the OEMs expressed concern over unrealistic technology uptake rates in the proposal. From 6x2 drivetrains to engine shutdown timers, speed limiters and even untried technologies such as waste heat recovery, the OEMs say EPA and NHTSA rates have to be revised to reflect real world conditions.

There are several references in the comments to incorrect assumptions about which “fuel economy bin” a truck might fit into given a specific set of parameters. Several OEMs have demonstrated that EPA has set impractically high targets for certain types of trucks. Those assumptions, they say, will set the bar impossibly high, and in some cases result in the downgrading or disqualification of some models.  

The OEMs want to see credit given where credit is due. One cited various electrical accessories that could earn credits under the proposal, such as electrically controlled air compressors or water pumps, while mechanically clutched components or those with variable speed operation could not. Another example is TPMS vs ATIS. So far, EPA seems willing to credit automatic tire inflation systems but not tire pressure monitoring systems. Both help keep tires at proper inflation pressures.

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Expressing concern about the cost of physically testing trucks and components, the OEMs are asking to use calculated values instead where it’s appropriate. One cited the burden of running about 130 tests to demonstrate deep powertrain integration at a cost of about $8.5 million. On top of that, the OEM would have to retest for each calibration it released. Those extra costs would have to be passed along.

This article barely scrapes the surface of what’s contained in the OEM comments to the proposal. Some of the changes they are asking for are highly technical in nature, and therefore indescribable in just a few hundred words. Others relate to testing and verification and compliance margins and stringency, and are equally difficult to describe. It’s enough to know that some of the test protocols EPA and NHTSA are proposing for this rule come without margins, where previously there were margins. In some cases, the OEMs say, to pass the test including the known but not acknowledged margins for error, the test results would have to be twice as stringent as would normally be the case.

Clearly there’s much work still to be done, and not a lot of time to do it.

Editor-in-Chief Deborah Lockridge contributed to this story.

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