"Diesels also are holding their own in the market for used heavy-duty trucks. Automotive Lease Guide's Blair says a diesel engine typically adds $6,000 to the sticker price of a new full-sized pickup. After 36 months, he estimates, the diesel engines will keep 60 percent of their value as an option, while the trucks themselves will retain only 47 percent of their value.

Glenn Romines, a Ford-Lincoln-Mercury dealer in Houston, Mo., says he sells 7 to 10 used diesel pickups a month. This month, he says, he paid $23,000 for a 2002 Ford F-350 - about $2,000 more than its guidebook wholesale value. Romines says he sold the truck for $24,500 - roughly $1,500 more than its prevailing retail price.", AutoWeek reports.