In the NPRM, EPA and NHTSA relied on three studies to estimate the cost of vehicle mass 

reduction. The NPRM used a value of $1.32 per pound of mass reduction that was derived from a 2002 

National Academy of Sciences study, a 2008 Sierra Research report, and a 2008 MIT study. The cost was 

estimated to be constant, independent of the level of mass reduction.

The agencies along with the California Air Resources Board (CARB) have recently completed work 

on an Interim Joint Technical Assessment Report (TAR) that considers light-duty GHG and fuel economy 

standards for model years 2017 through 2025 and have continued this work to support the light-duty 

vehicle NPRM, which is expected to be issued this fall. Based on new information from various industry 

and literature sources, the TAR report modified the mass reduction/cost relationship used in the 2012-

2016 light-duty final rules to begin at the origin (zero cost at 0% mass reduction) and to have increasing 

cost with increasing mass reduction.i The resulting analysis showed costs for 5% mass reduction on lightduty vehicles to be near zero or cost parity. 

In the proposal for heavy-duty vehicles, we estimated mass reduction costs based on the 2012-2016 

light-duty analysis without accounting for the new work completed in the Interim Joint Technical 

Assessment and additional work the agencies have considered for the light-duty vehicle NPRM. Since the 

heavy-duty vehicle proposal, the agencies have been able to consider updated cost estimates in the context 

of both light-duty and heavy-duty vehicle bodies of work. While the agencies intend to discuss the 

additional work for the light-duty NPRM in much more detail in the documents for that rulemaking, we 

think it appropriate to explain here that after having considered a number of additional and highly-varying 

sources, the agencies believe that the cost estimates used in the TAR may have been lower than would be 

reasonable for HD pickups and vans, given their different and work-related uses and thus different 

construction as compared to the light-duty vehicles evaluated in the TAR. We do not believe that all of 

the weight reduction opportunities for light-duty vehicles can be applied to heavy-duty trucks. However, 

we do believe reductions in the following components and systems can be found that do not affect the 

payload and towing requirements of these heavy-duty vehicles; body, closure panels, glazing, seats and 

other interior components, engine cooling systems and HVAC systems. 

The agencies have reviewed and considered many different mass reduction studies during the 

technical assessment for the heavy-duty vehicle GHG and fuel efficiency rulemaking. The agencies 

found that many of the studies on this topic vary considerably in their rigor, transparency, and 

applicability to the regulatory assessment. Having considered a variety of options, the agencies for this 

heavy-duty analysis have been unable to come up with a way to quantitatively evaluate the available 

studies. Therefore, the agencies have chosen a value within the range of the available studies that the 

agencies believe is reasonable. The studies and OEM confidential business information relied upon in 

determining the final mass reduction cost are summarized below in Figure Error! No text of specified 

style in document.Error! No text of specified style in document.-1. Each study relied upon by the 

agencies in this determination has also been placed in the agencies’ respective dockets. See NHTSA2010-0079; EPA-HQ-0AR-2010-0162.
Figure Error! No text of specified style in document.Error! No text of specified style in document.-1: Mass 

Reduction Cost Data Considered for Final Rulemaking

Thus, we are estimating the direct manufacturing costs for a 5 percent mass reduction of a 6,000 lb 

vehicle at a range of $75-$90 per vehicle. With additional margin for uncertainty, we arrive at a direct 

manufacturing cost of $85 -$100, which is roughly in the upper middle of the range of values that resulted 

from the additional and highly-varying studies mentioned above that were considered in the agencies’ 

review. We have broken this down for application to HD pickup trucks and vans as follows: Class 2b 

gasoline $85, Class 2b diesel $95, Class 3 gasoline $90, and Class 3 diesel $100. Applying the low 

complexity ICM of 1.24 results in estimated total costs for a 5 percent mass reduction applicable in the 

2016 model year of: Class 2b gasoline $108, Class 2b diesel $121, Class 3 gasoline $115, Class 3 diesel 

trucks $127. All mass reduction costs stated here are in 2009 dollars. 

 

i

“Interim Joint Technical Assessment Report: Light-Duty Vehicle Greenhouse Gas Emission Standards and 

Corporate Average Fuel Economy Standards for Model Years 2017-2025;” September 2010; available at 

http://epa.gov/otaq/climate/regulations/ldv-ghg-tar.pdf and in the docket for this rule.