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EPA Fuel economy figures are presented for model year 1982 cars and light duty trucks. Comparisons with the MPG figures of prior years are included. Sales penetrations of various vehicle, engine, and emission control design features are given, and domestic cars' MPG characteristics are compared to that of imports', gasoline vehicle MPG is compared to Diesel MPG, and 49-states MPG is compared to California MPG. Usage of newer vehicle technologies is continuing to increase, leading to continued growth in fuel economy capability in spite of stringent emission standards.

This is an analysis of fuel economy data compiled by the U.S. EPA on passenger cars from model years 1958-1978, and light-duty trucks from 1975-1978. The paper includes new fuel economy data on pre-1975 cars, which indicates that fleet average MPG for the older models is slightly higher than had been previously estimated. Analysis of 1977-78 passenger cars and light trucks' economy characteristics in terms of the new EPA/DOE “Vehicle Size” classes provides new insight into fleet MPG characteristics as related to model changes. The methodology for isolating fleet and individual manufacturer fuel economy changes due to specific factors such as system optimization and weight mix shifts has been refined, and is applied for the first time to trucks and to comparison of 49-states and California vehicles. The vehicle fleet which is the basis of the analysis includes the top-selling 18 car makers and 8 truck manufacturers.

EPA new-model fuel economy figures are presented for passenger vehicles and light duty trucks (those with GVW ratings up to 8500 lbs). The 1981 models are emphasized, with some comparisons to prior years included. Reader familiarity with the EPA tests, data bases, and analytical methods is assumed. Principal two-way analyses include comparisons of domestic vs. import, gasoline vs. Diesel, and Federal (49-state) vs. California vehicles. Sales fractions for a number of vehicle and engine emission control design features are included. The principal finding is that increased use of newer vehicle and emission control technologies in 1981 has accompanied significant fuel economy gains in spite of the tougher 1981 emission standards.

The fuel economy data compiled by the U.S. Environmental Protection Agency (EPA) have been analyzed to determine the trends in passenger car fuel economy beginning with model year 1958. Light duty truck fuel economy has been examined beginning with the 1976 model year. This paper adds the 1977 model year data to the historical trend and concentrates on the comparisons between the 1976 and 1977 models and the 1977 California and 49-state fleets. Calculation procedures have been used on the passenger car data which allow the changes in fuel economy due to system optimization, new engine/vehicle combinations, and weight mix shifts to be determined separately for individual manufacturers and the fleet as a whole. The passenger car fleet consists of the 13 manufacturers which were certified by September 13, 1976. Seven manufacturers comprise the light duty truck fleet.

The pre-1975 EPA fuel economy data base has been expanded to over 6,600 cars, and these data on older cars have been adjusted for odometer mileage effects on fuel economy. The data base for model year 1975-1977 certification cars is also updated, reflecting actual sales figures. The resulting trend analyses are thus (for the first time) consistent from year to year with regard to the representation of actual sales weighted new-car fleet fuel economy. Data on the 1979 fleet is presented in detail, and compared with that of the 1978 fleet, on the basis of projected sales for those two years. Comparisons with pre-emission control MPG, which serve as measures of technological change accompanying increasingly stringent emission standards, are accordingly revised from previous publications (1)* on this subject.

This, the eleventh in a series of Papers on EPA fuel economy trends, emphasizes the current Model Year (1983) as usual, but also gives increased emphasis to trends in vehicle technology, including catalyst and transmission subclasses. Final “CAFE”* production volumes and MPG figures have been used to update the data bases through the 1980 Model Year, and an analytic method used in the past to allocate year-to-year fleet MPG changes to specific causes, such as weight mix shifts, has been reinstituted. Conclusions are presented on the relation between fuel economy and emission standards, catalyst types, and transmission types.

This, the fourteenth in this series of papers, examines trends in fuel economy, technology usage and estimated 0 to 60 MPH acceleration time for model year 1986 passenger cars. Comparisons with previous year's data are made for the fleet as a whole and using three measures of vehicle/engine size: number of cylinders, EPA car class, and inertia weight class. Emphasis on vehicle performance and fuel metering has been expanded and analysis of individual manufacturers has been deemphasized; comparisons of the Domestic, European, and Japanese market sectors are given increased emphasis.

This, the fifteenth in this series of papers, examines trends in light-duty vehicle fuel economy and technology usage for model years 1978 through 1987. Comparisons with previous years’ data are made for the fleet as a whole and for number of cylinders, vehicle size class, inertia weight class, and market segment (Domestic, European, and Asian).

Light duty truck fuel economy trends from model year 1975 through 1984 are examined, with special emphasis placed on model year 1984. Actual production volumes are given for model years 1975 through 1982. Data for 1983 and 1984 model years include EPA estimates of sales, in which projected sales data submitted by manufacturers were adjusted using the same procedure as described in (1)*. For fuel economy trend analysis, a modified truck classification system is presented and discussed. In addition, the model year 1975 to model year 1979 light truck data bases have been updated to include those trucks with gross vehicle weights (GVWs) between 6000 and 8500 lbs; accordingly the paper treats all model year trucks from 1975 through 1984 as 0-8500 lb GVW fleets. This paper, along with the passenger car fuel economy trends paper (1), gives a complete picture of fuel economy trends through 1984. Combined car/truck fleet analyses are presented in Appendix A.

The offset (sometimes called “shortfall”) between EPA MPG and actual in-use MPG has been shown to be dependent upon vehicle technology and EPA MPG level. If these variables change significantly, there is the potential for the constant EPA MPG adjustment factors (0.90 city, 0.78 highway) to become obsolete. Trends in passenger car MPG have been used to formulate a model of vehicle technology mixes and MPG levels over the next 15 years, to investigate the degree to which MPG adjustments derived from such a scenario might differ from the promulgated constant adjustment factors. As a check on the reasonableness of the future technology scenario, a simple econometric model was constructed independently which relates car class market fractions and MPG levels to gasoline price, and to regulatory requirements: MPG Standards and the Gas Guzzler tax.

This paper develops and discusses the 1978-85 time trends in alternative measures of vehicle fuel economy. Nine alternative measures are presented ranging from ton-miles per gallon to menu-weighted performance adjusted miles per gallon. For each alternative measure, trends for important groups of manufacturers are presented. Ail of the trends in alternative measures are compared to the percent improvement implied by the original 1978 and 1985 passenger car average fuel economy standards (AFES).