Can't wait to trade in the old family wagon for a shiny new vehicle? Crave that new car smell?

Uncle Sam is dealing.

The Car Allowance Rebate System, also known as the "Cash for Clunkers" law, was signed into law by President Barack Obama last month, although it may take several weeks before consumers will be able to collect on the offer.

The legislation makes vouchers of $3,500 to $4,500 available to buyers who trade in their old, gas-guzzling cars for new, fuel-efficient models. Local dealers say the taxpayer-supported incentives may be just what the auto industry needs to pull out of its nosedive.

"It would help the sale of new cars, which have been floundering," said Mansfield Chrysler Jeep dealer Paul Connor. "It would also help save fuel and the environment." South Attleboro General Motors dealer Al Cerrone said the incentives could give an immediate lift to auto dealers and manufacturers, particularly those who have models to offer that get well above the federal standard.

Because of an aging national fleet, it's likely there will be plenty of people motivated to buy.

The proposed incentives would also combine with auto maker rebates to make cars far more affordable, Cerrone said.

"With the incentives manufacturers are offering, when you add in these kind of rebates, buyers could get up to 50 percent off the list price of their new vehicle," he said.

According to a government Web site, rebates won't be available right away. Regulations have yet to be written and dealers will need to sign up for the program.

Even once government incentives become available, not every car owner would benefit, according to a summary of the new law.

To qualify, a trade-in would have to be no older than 1984 and would have to be EPA-rated at 18 mpg or less. The new car the consumer is purchasing would have to get at least 22 mpg.

If the mileage of the new car is at least 4 mpg higher than the old vehicle, the voucher will be worth $3,500. If the mileage of the new car is at least 10 mpg higher than the old vehicle, the voucher will be worth $4,500.

The program was supported by the Automobile Dealers Association of Alabama and the National Automobile Dealers Association as a means of jump starting new vehicle sales and encouraging consumers to purchase clean, fuel-efficient vehicles.

"Coupled with the current deductibility of vehicle sales taxes paid from federal income tax, there has never been a better time to purchase a new vehicle," said Tom Dart, President of the Automobile Dealers Association of Alabama. The National Highway Transportation Safety Administration has created a Web site for the Car Allowance Rebate System (CARS) - www.cars.gov - to provide consumers information on the specifics of the program.