Order Code RS20298
Updated June 28, 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
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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emissions 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
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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(e.g. Toyota Tacoma). The next category, LDT2, includes most light pickups, all mini-
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. (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
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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economy can be 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, CAFE provisions in
both the House and Senate versions of comprehensive energy legislation proved
especially controversial. H.R. 4, the comprehensive energy package, passed the House
on August 2, 2001, and the Senate on April 25, 2002. The CAFE-related provisions of
these two versions are substantially different, especially in their treatment of light trucks.13
The Senate version of H.R. 4 contains several provisions relating to fuel economy.
Most notably, the Senate version would require NHTSA to issue increased fuel economy
standards (for passenger cars, SUVs, mini-vans) within 15 months of enactment of the bill
(Section 801). If new standards are not enacted, Congress may establish new CAFE
standards under expedited procedures (Section 802). However, Section 811 would freeze
CAFE standards for “pickup trucks” at 20.7 mpg and preclude NHTSA from issuing any
future CAFE increases for pickups. NHTSA has not previously defined the term “pickup”
as it relates to fuel economy standards. Therefore, it remains to be seen which vehicles
would be covered under this standard. The House version of H.R. 4 requires NHTSA 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. On June 28,
2002, the Conference committee convened to reconcile the two versions of this bill.
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.
13 For a detailed analysis of this bill, see CRS Report RL31427, Omnibus Energy Legislation:
H.R. 4 Side-by-side Comparison.

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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.14 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.15 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.16 Under the new “Tier 2” standards,
all light trucks and passenger cars, as well as medium-duty SUVs and passenger vans, will
be held to the same emissions standards by MY2009.17
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.”18 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 emissions control 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
14 International Harvester Co. v. Ruckelshaus, D.C. Cir. No. 72-1517, Feb. 10, 1973.
15 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.
16 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.
17 CRS Report RS20247: EPA’s Tier 2 Proposal for Stricter Vehicle Emission Standards: A Fact
Sheet.
18 64 Federal Register 26035. May 13, 1999.

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November 1998, California ruled that beginning in MY 2004, all light trucks must meet
the same emissions standards as passenger cars.19
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.20 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.21 Furthermore, they argue that emissions reductions could be
achieved with considerably smaller cuts in the sulfur level.22 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 1997.23 These revised standards were remanded to EPA for further
consideration by the U.S. Court of Appeals in May 1999.24 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.25
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.
19 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.
20 Fore more information, see CRS Report RS20163: Sulfur in Gasoline.
21 Testimony of J. Louis Frank, President, Marathon Ashland Petroleum before the Senate
Committee on Environment and Public works. May 18, 1999.
22 Testimony of Clint W. Ensign, Vice President, Government Relations, Sinclair Oil Corporation
before the House Committee on Science. July 21, 1999.
23 64 Federal Register 38652-38896. July 18, 1997.
24 American Trucking Ass’ns v. EPA, D.C. Cir. No. 94-1440, May 14, 1999.
25 64 Federal Register 35112-35119. June 30, 1999.

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