WASHINGTON, March 28 — The Transportation Department will announce a fuel economy standard for sport utility vehicles, vans and pickups on Wednesday that for the first time will cover vehicles above 8,500 pounds, and will differ in how it categorizes vehicles, according to people briefed on the rule.
Last year the Transportation Department published a draft rule that would have divided the category now called "light trucks" into six categories, based on vehicle size, and set mileage standards within each size, to encourage manufacturers to make vehicles that get as many miles a gallon as possible.
But policy makers decided in the last few weeks that this would merely encourage manufacturers to "game the system," as one government official involved in creating the rule put it, by making an S.U.V. slightly bigger so that it could move up a category and meet a lower fuel economy standard. Auto makers already move some vehicles into the light-truck category from the car category, to allow lower fuel economy.
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Experts said that the average number of miles a gallon that light trucks would achieve under the new standard, which will cover the years 2008 through 2011, would be difficult to predict, and would depend on the mix of vehicles sold.
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http://www.nytimes.com/2006/03/29/business/29epa.html?_r=1&oref=slogin