Order Code RS20298
Updated February 21, 2002
CRS Report for Congress
Received through the CRS Web
Sport Utility Vehicles, Mini-Vans and Light
Trucks: An Overview of Fuel Economy and
Emissions Standards
Brent D. Yacobucci
Environmental Policy Analyst
Resources, Science, and Industry Division
Summary
Most sport utility vehicles, mini-vans, and pickups are classified as “light trucks”
and thus are regulated less stringently than passenger cars under two major laws—the
Energy Policy and Conservation Act for fuel economy standards, and the Clean Air Act
for emissions standards. These differences came about because at the time the laws were
passed, light trucks were used differently, and because they represented a much smaller
share of the automobile market. Over the past decade, however, these vehicles have
dramatically increased their share of the new automobile market. Therefore, the share
of total fuel consumption and emissions attributable to these vehicles has steadily
increased. In response to this trend, the Environmental Protection Agency has ruled that
by model year 2009, emissions from all light trucks and passenger cars will be regulated
equally. However, between fiscal years 1996 and 2001, provisions in the Department of
Transportation’s (DOT) annual appropriations prohibited DOT from changing fuel
economy standards. The issue for Congress is whether these vehicles should continue
to be treated differently from passenger cars. This report discusses the discrepancy
between emissions and fuel economy standards for passenger cars and light trucks, how
that discrepancy is changing, and legislative activity related to these issues.
Introduction
Sport utility vehicles and other light trucks are regulated through two laws that affect
their fuel use and emissions: the Energy Policy and Conservation Act of 1975 (EPCA)1
and the Clean Air Act (CAA).2 EPCA first set fuel economy standards for the 1977 model
year (MY1977). Since then, all light trucks—including most sport utility vehicles (SUVs)
and all mini-vans—have been held to less stringent fuel economy standards than passenger
cars. Furthermore, since MY1975, most light trucks have faced less stringent emissions
1 P. L. 94-163, Section 301; 49 U.S.C. 32902.
2 42 U.S.C. 7521.
Congressional Research Service ˜ The Library of Congress

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standards under Clean Air Act regulations. The differences in standards reflected the
situation prevalent at the time these laws were enacted: first, light trucks were mainly used
as commercial and agricultural work vehicles3; second, they were a relatively small portion
of the U.S. automobile market.
Since then, conditions have changed significantly. Today, light trucks are a larger
portion of the total vehicle population, and travel more annual vehicle miles. For example,
in 1980, light trucks composed 19.9% of the U.S. new automobile market.4 By 1999, this
figure had increased to 48.3%; SUVs alone accounted for 18.6% of the new vehicle
market in 1999, while mini-vans accounted for 7.9%.5 However, a comparison of market
share underestimates this growth and its consequences. While the number of passenger
cars sold each year in the United States has decreased somewhat since 1980, the number
of light trucks sold has more than tripled, from 2.2 million in 1980 to 8.2 million in 1999.
In 1999, SUV sales alone (3.1 million) exceeded total light truck sales for 1980. As a
result, the total fuel usage and emissions attributable to these vehicles has increased.
Because of the increased emissions from light trucks, the Environmental Protection
Agency (EPA) has ruled that by MY2009, all light vehicles (including all passenger cars
and SUVs, and most vans and pickups—all but the very largest vehicles) will be held to
the same emissions standards. Congress prohibited similar action regarding fuel economy
through provisions in annual appropriations bills for the Department of Transportation
(DOT) between FY1996 and FY2001.6
Definition of “Light Truck”
For the purposes of fuel economy standards, DOT defines a light truck as any truck
or “truck derivative” with a gross vehicle weight rating (GVWR) of 8,500 pounds or less,
and a vehicle curb weight (VCW) of 6,000 pounds or less.7 (49 CFR 523) SUVs and
mini-vans are usually built on truck chassis, or have other truck-like characteristics (e.g.
4 wheel drive and/or flat loading areas), and are therefore classified as light trucks.
EPA uses the same basic definition of a light truck, under the current “Tier 1”
emissions standards. However, a distinction is made between different vehicle types
(Light-Duty Truck 1 through 4), based on GVWR and either loaded vehicle weight
(LVW) or adjusted loaded vehicle weight (ALVW).8 The Light-Duty Truck (LDT) 1
category includes compact SUVs (e.g. Chevrolet Tracker) and a few small pickup trucks
(e.g. Toyota Tacoma). The next category, LDT2, includes most light pickups, all mini-
3 Heavier-duty uses generally require greater vehicle weight, which tends to increase emissions and
decrease fuel economy.
4 Automotive News. The 100-Year Almanac and 1996 Market Data Book. p. 120.
5 Automotive News. 2000 Market Data Book. p. 50.
6 The most recent being the Department of Transportation and Related Agencies Appropriations
Act, FY2001, P.L. 106-346.
7 GVWR: the weight of the vehicle plus the designed maximum load capacity. VCW: the weight
of the vehicle with all standard equipment and the fuel tank at nominal capacity.
8 LVW: VCW plus 300 pounds. ALVW: average of VCW and GVWR.

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vans and most SUVs (e.g. Ford Explorer). The LDT3 and LDT4 categories include full-
sized pickups, passenger vans and larger SUVs (e.g. Dodge Durango).
Finally, some SUVs and pickups are so large (greater than 8,500 lbs. GVWR) that
they do not qualify as “light trucks” under the current standards. These include the largest
full-sized pickups, passenger vans, and SUVs. However, EPA recently added the
classification “medium-duty passenger vehicle” to include heavy passenger
vehicles–passenger vans and SUVs up to 10,000 GVWR starting in MY2004. Heavy
pickups and cargo vans will not be affected, since their main function is transporting cargo,
as opposed to passengers.9 This change is only for emissions standards, and will not affect
fuel economy standards. However, legislation has been introduced that would regulate
the fuel economy of these vehicles. (See “Congressional Concerns and Activity” in the
following section)
Fuel Economy Standards
The Energy Policy and Conservation Act requires Corporate Average Fuel Economy
(CAFE) standards for motor vehicles. Under the standards, the average fuel economy of
all vehicles of a given class that a manufacturer sells in a model year must be equal to or
greater than the standard. These standards were first enacted in response to the desire to
reduce petroleum consumption and promote energy security after the Arab oil embargo.
The current law sets the CAFE standard for passenger cars at 27.5 miles per gallon (mpg).
Furthermore, this law gives DOT the authority to define other classes of vehicles, and set
fuel economy standards for those vehicles. Currently, the average fuel economy of light
trucks—as they are defined above—is regulated at 20.7 mpg. (49 CFR 533)

Fuel economy standards for light trucks were steadily tightened through the 1980s
and early 1990s, and were completely standardized (for all light truck sub-classes) in
MY1996. Passenger car standards have remained unchanged since MY1990. DOT has
the regulatory authority to set CAFE standards for a given model year taking into account
technological feasibility, economic practicability, other vehicle standards, and the need to
conserve energy. Since fiscal year 1996 (FY1996), however, through annual
appropriations bills, Congress has expressly prohibited DOT from using any funds to
change CAFE standards. Because DOT may not spend money to “prepare, propose or
promulgate any regulations...prescribing [revised] fuel economy standards,”the standards
have remained constant.10
For FY2001, the Senate agreed to accept this CAFE language only if DOT, along
with the National Academy of Sciences, was permitted to conduct a study of fuel economy
and recommend appropriate CAFE standards (P.L. 106-346). The law required the study
take into account the factors outlined in EPCA (feasibility, economics, and energy
conservation), as well as vehicle safety and the effects on the auto industry. However, for
DOT to promulgate new standards, the recommendations would need to be approved by
a joint resolution of Congress. The panel concluded that light truck fuel economy can be
9 Environmental Protection Agency (EPA), Regulatory Announcement: EPA's Program for
Cleaner Vehicles and Cleaner Gasoline. December 21, 1999.
10 For more information on CAFE standards, see CRS Issue Brief IB90122: Automobile and Light
Truck Fuel Economy: Is CAFE Up to Standards?

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increased without significant cost increases and without harming the auto industry, if given
significant lead time.11 The National Energy Policy Report, produced by the Bush
Administration, recommends that DOT review and provide recommendations on
increasing CAFE standards, taking into account the NAS study.12
Issues. Regulation of SUVs and light trucks is a contentious issue. Some
environmentalists argue that these vehicles waste fuel and pollute excessively. Meanwhile,
vehicle manufacturers and other interest groups argue that tougher regulation of these
vehicles would limit consumer choice in the market.
Even though the CAFE provisions in EPCA were not enacted for the purpose of
achieving environmental goals, some environmentalists argue that increased fuel economy
would promote better air quality, reduce greenhouse gas emissions, limit dependence on
foreign oil, and lower consumer expenditures at the pump. Meanwhile, U.S. automobile
industry spokespersons argue that CAFE standards have little or no effect on oil imports,
promote more consumption (through lower annual fuel costs), and give an advantage to
foreign manufacturers (which produce smaller vehicles). In addition, since EPCA only
addresses the need to conserve energy, environmental justifications for tougher standards
have been challenged by opponents. Moreover, some consumer groups argue that CAFE
standards lead to decreased vehicle safety, because a common method for reducing fuel
consumption is to reduce vehicle weight.
Congressional Concerns and Activity. CAFE standards have been an issue
in congressional debates over DOT funding since FY1996. Further, four bills have been
introduced in the 107th Congress that address light truck fuel economy.
Two bills, H.R. 1815 (Olver) and S. 804 (Feinstein) would explicitly raise light truck
fuel economy standards to the passenger car standard of 27.5 miles per gallon by 2007.
Further, these bills would require fuel economy standards for heavier trucks (between
8,500 and 10,000 pounds gross weight). H.R. 2614 (Miller, George) would require
phased CAFE increases for both passenger cars and light trucks. By MY2007, the bill
would require a combined car and truck fuel economy of 32.0 mpg, increasing to 40.0 mpg
by MY2011. H.R. 2614 would also require fuel economy standards for heavier trucks. All
three bills have been referred to committee.
In addition to these bills, Congress is currently considering comprehensive energy
legislation. H.R. 4 (Tauzin), which passed the House on August 2, 2001, also addresses
light truck fuel economy. The bill requires DOT to set light truck fuel economy standards
for MY2004 to MY2010 such that at least 5 billion gallons of gasoline are saved compared
to vehicles produced in MY2002. In the Senate, S. 517 (as amended by S.Amdt. 2917),
would require much more significant changes to the fuel economy standards. First, the bill
would require much higher standards for passenger cars and light trucks starting in
MY2005, and would require a combined car and truck fuel economy of 35 mpg by
MY2013. Floor debate is expected on the Senate bill beginning the week of February 25,
2002.
11 National Academy of Sciences, National Research Council, Effectiveness and Impact of
Corporate Average Fuel Economy (CAFE) Standards. Washington, D.C. 2002.
12 National Energy Policy Development Group, National Energy Policy. May 2001. p. 4-9.

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Emissions Standards
Before 1975, all light trucks were classified by EPA as “light duty vehicles”, i.e.
passenger cars. However, in a case brought by International Harvester, the U.S. Court of
Appeals concluded that light trucks should be classified differently, due to the agricultural
and commercial nature of their use.13 Therefore, light trucks were given their own
classification and have faced less stringent emissions standards since MY1975. Under the
current CAA “Tier 1” standards, light trucks are allowed to emit higher levels of pollution
with each heavier weight class. Furthermore, Tier 1 standards for light trucks are
generally less stringent than those for passenger cars. Only vehicles in the LDT1 class
meet the same standards as passenger cars.14 Most SUVs and pickups, and all vans, are
currently permitted to emit 29% to 47% more carbon monoxide (CO) and 75% to 175%
more nitrogen oxides (NO ) than passenger cars. (40 CFR 86)
x
Tier 2 Standards. The Clean Air Act gives EPA the authority to set standards for
MY2004 and beyond, in order to attain and maintain the National Ambient Air Quality
Standards (NAAQS). However, EPA may only tighten emissions standards if the
technology to do so is available and cost-effective. On February 10, 2000, EPA finalized
new standards for passenger cars and light trucks.15 Under the new “Tier 2” standards,
all light trucks and passenger cars (up to 8,500 pounds GVWR) will be held to the same
emissions standards by MY2009.16
Three primary factors influenced EPA’s decision: use patterns, market share, and
technology. First, according to EPA, today these vehicles “are used like passenger cars
and there are more annual miles traveled as a result.”17 Since these vehicles travel more
miles per year, emissions attributable to the average vehicle have increased. Second, as
was stated above, there are simply more light trucks on the road today. Because of the
increased number of these vehicles, the contribution of the emissions from these vehicles
to vehicular air pollution has similarly increased. Finally, EPA chose to set such stringent
standards for light trucks because new catalytic converter technology is available to permit
cuts in emissions without decreasing weight or power, and without generating excessive
costs for automobile manufacturers or consumers.
As in many cases over the past thirty years, EPA is following the lead of California,
which has the most stringent automobile emissions standards in the country. In November
13 International Harvester Co. v. Ruckelshaus, D.C. Cir. No. 72-1517, Feb. 10, 1973.
14 These vehicles (compact SUVs and pickups) comprise approximately 17% of the light truck
market. Source: EPA. Office of Mobile Sources. Tier 2/Sulfur Draft Regulatory Impact
Analysis. April 1999. p. V-25.
15 EPA, Control of Air Pollution from New Motor Vehicles: Tier 2 Motor Vehicle Emission
Standards and Gasoline Sulfur Control Requirements; Final Rule. 65 Federal Register 6698.
February 10, 2000.
16 CRS Report RS20247: EPA’s Tier 2 Proposal for Stricter Vehicle Emission Standards: A Fact
Sheet.
17 64 Federal Register 26035. May 13, 1999.

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1998, California ruled that beginning in MY 2004, all light trucks must meet the same
emissions standards as passenger cars.18
Issues. The Tier 2 standards have raised three major issues among vehicle
manufacturers, oil refiners and environmentalists:
First, because the heaviest vehicles are exempt from the Tier 1 emissions standards
(since they are not considered “light trucks”), some environmental groups were concerned
that automobile manufacturers would be motivated to “bulk up” their heavier light trucks,
placing them in the heavy truck class, to avoid improving their emissions. Therefore, EPA
added the class of “medium-duty passenger vehicles” to include these vehicles.
Second, with existing technology, emissions reductions are dependent on reductions
in the sulfur content of gasoline.19 Therefore, EPA also promulgated more stringent limits
on gasoline sulfur content. Oil refiners acknowledged that sulfur does affect emission
controls, but claimed that their input was ignored in the rule-making process, and that the
timeline for the rule will greatly increase the cost of gasoline, and will push smaller refiners
out of the market.20 Furthermore, they argue that emissions reductions could be achieved
with considerably smaller cuts in the sulfur level.21 Conversely, automobile manufacturers
have argued that emissions reductions are unattainable without sulfur reductions, and have
expressed support for even greater reductions.
Third, the oil refining industry has questioned whether EPA’s justification of the Tier
2 standards relies on the revised NAAQS for ozone and particulate matter, which EPA
promulgated in July 1997.22 These revised standards were remanded to EPA for further
consideration by the U.S. Court of Appeals in May 1999.23 In June 1999, to deter
potential legal challenges to the Tier 2 standards, EPA issued a notice that justifies the Tier
2 standards under the previous NAAQS standards for ozone and particulate matter, which
still apply to states that have not yet achieved attainment.24
Congressional Concerns and Activity. No legislation has been introduced in
the 107th Congress on emissions, but vehicle emissions standards are a matter of
congressional oversight.
18 CAA allows states to adopt California emissions standards in lieu of the federal standards. In
the absence of action by EPA, a number of states planned to adopt the California standards. Auto
manufacturers, not wanting to face multiple standards, have been generally supportive of Tier 2.
19 Fore more information, see CRS Report RS20163: Sulfur in Gasoline.
20 Testimony of J. Louis Frank, President, Marathon Ashland Petroleum before the Senate
Committee on Environment and Public works. May 18, 1999.
21 Testimony of Clint W. Ensign, Vice President, Government Relations, Sinclair Oil Corporation
before the House Committee on Science. July 21, 1999.
22 64 Federal Register 38652-38896. July 18, 1997.
23 American Trucking Ass’ns v. EPA, D.C. Cir. No. 94-1440, May 14, 1999.
24 64 Federal Register 35112-35119. June 30, 1999.

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