In May, the Federal Trade Commission began accepting public comment on whether the guidelines should be reviewed and modified. The written comment period ends July 23.
The guide, which applies only to new vehicles, dates to 1975. It is designed "to prevent deceptive fuel economy advertising and to facilitate the use of fuel economy information in advertising," according to the FTC.
The possible FTC review is due in part to recent fuel economy action by the EPA. In the 2008 model year, the government begins a new way of estimating fuel economy meant to better reflect real-world driving conditions.
Automotive marketers expect fuel economy estimates to decline on advertised 2008 models. But overall marketing strategies are unlikely to be affected, automakers say.
"Everyone is adjusting relative to each other," says Chuck Schifsky, a spokesman for American Honda Motor Co. Inc. "Everybody's numbers will be going down, but the difference between competitors will stay the same."
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