Anyone thinking about trading in that gas-guzzling SUV for a fuel-efficient compact should consider that the payback in fuel savings could be a long time coming. And those savings could be eaten up quickly by new car payments for those hot new compacts, according to experts quoted in an article by Newsday.

While it might be tempting to trade in your big SUV, it's important you take everything into consideration, or you may end up spending thousands to save hundreds, according to the Kelley Blue Book car price service.

Jack Gillis, a spokesman for the Consumer Federation of America and the author of "The Car Book," a buying guide, also says consumers should be careful before unloading their SUVs.

Tom Kontos, chief economist for Indiana-based ADESA Inc., which operates 60 North American dealer actions, said compact cars are worth an average of 10 percent more than they were a year ago. "They were also 2.5 percent higher in May than they were in April," he said.John Burns Jr., owner of Honda City in Levittown, said new and used Civics are in tight supply -- used ones in particular.

Paul Taylor, chief economist for the National Automobile Dealers Association, said in the Newsday article that if gasoline prices fall, SUV values are likely to rebound, as they have in the past, so it might make sense to wait before dumping that SUV.