Old habits are hard to break.
So even though the federal government is preparing a historic revision in how it calculates vehicle fuel economy, one thing will not change: Fuel economy ratings will be reported in the familiar miles-per-gallon format, not in terms of gallons consumed per distance traveled - despite requests for a switch from Toyota and Honda executives.
At last year's Management Briefing Seminars, Dave Hermance, executive environmental engineer at Toyota Technical Center U.S.A., revealed that Toyota and Honda had approached the federal government about a possible change.
Federal law limits the changes regulators can make, and the motoring public is too accustomed to the three-decade-old miles-per-gallon metric for it to be dropped, the companies admit.
"It's not ripe," says Ed Cohen, vice president for government and industry relations at Honda North America Inc.
But that doesn't mean the automakers' claim of a better way to report vehicle fuel consumption has fallen on deaf ears.
Hermance says the EPA is considering an addition to fuel economy labels on vehicle windows. The new section would be similar to an energy guide on an appliance, which shows how much power the device is expected to use in a year compared with competitive models.
Rules, likely to be issued late this year, would provide for the label additions. The main purpose of the rules is to make fuel economy estimates more accurate, that is, closer to what motorists get in real-world driving.
"It's going forward in a pretty reasonable manner," Hermance concludes, based on company conversations with EPA officials.
Agency spokesman John Millett confirms only that a proposal should be ready by year end.
"It's too soon to rule anything in or out," Millett says.
The EPA reviewed its method of calculating fuel economy ratings for new cars and trucks after getting complaints from motorists and receiving a petition from environmental group Bluewater Network.
Motorists complained that they often don't get the gasoline mileage estimated by the EPA.
The petition said driving habits and traffic conditions have changed, and the EPA's calculation method, adopted in 1974 and revised in 1984, is outdated.
The basic method is this: In the course of doing emissions testing, the EPA also determines how far a vehicle goes on a gallon of gasoline in a city driving cycle and in a highway driving cycle.
To reflect real-world conditions, not laboratory conditions, the city number is adjusted downward by 10 percent and the highway number by 22 percent.
The results go on window stickers and into the government's fuel economy guide.
Some members of Congress are trying to enact a measure requiring changes in the city and highway adjustment percentages.
Therese Langer, director of the transportation program at the nonprofit American Council for an Energy-Efficient Economy, says such simple change would be the wrong approach.
Langer says a better method would be to include in the estimates other laboratory test cycles already conducted by the EPA but so far not used in fuel economy calculations.