Pickup trucks and sport utility vehicles were big sellers under the Cash for Clunkers program despite the federal government's focus on replacing gas guzzlers with more fuel-efficient cars.

Data released late last week by the Department of Transportation shows that tens of thousands of trucks, minivans and SUVs with relatively low gas mileage were among the nearly 700,000 vehicles sold under the program in late July and August. It even included a handful of Hummers, a hulking vehicle not usually associated with fuel economy.

A major goal of Cash for Clunkers was to remove older and polluting vehicles from the road. In order to cash in on rebates of $3,500 to $4,500, car buyers had to buy new vehicles with better gas mileage than their trade-ins that were scrapped by dealers. For passenger cars, that difference had to be at least 4 mpg. But for buyers of SUVs, pickups and minivans, that difference had to be only 2 mpg.

That meant buyers trading in vehicles that dated back to the mid-1980s, well before manufacturers put a priority on fuel economy, could qualify for the credits while buying trucks and SUVs that get less than 20 mpg.

The data was the first account of all the new cars sold through the program — prior to last week, the government had only released a list of top-10 sellers, which was loaded with smaller vehicles with higher gas mileage like the Toyota Corolla and the Ford Focus.

The Corolla was the top-selling new vehicle, with 29,488 vehicles sold. It was followed by the Honda Civic with 28,456, the Toyota Camry with 27,137 and the Ford Focus with 22,388.

But some crossovers and pickups were also among the best-selling vehicles in the program when different versions of the vehicle were accounted for. The government's analysis had considered two-wheel and four-wheel versions of a car or truck to be a different vehicle.

The Ford Escape, for example, can be purchased with four-wheel drive or front-wheel drive, as a hybrid version or with an engine capable of running on flexible fuel such as E85 ethanol. All told, Ford sold 21,894 Escapes through the program, the fifth-most in the program. Honda sold 20,106 versions of the CR-V crossover — more than half of the CR-Vs were 2009 four-wheel-drive models.

Cash for Clunkers sales included 16,330 Chevrolet Silverado pickups when all models were taken into account. Ford, meanwhile, sold 16,263 F-150 pickup trucks, which come equipped with multiple engine assortments.

The Toyota Prius, meanwhile, a poster child for fuel efficiency, sold 15,013 vehicles through Cash for Clunkers, fewer than the Nissan Altima, Honda Accord and Toyota RAV4.

Some environmentalists had complained that the program would lead some consumers to trade in their clunkers to buy a Hummer. The data showed that 15 2009 Hummer H3T with four-wheel drive models were purchased through Clunkers.

Smart sold 1,152 fortwo micro cars through the program; Toyota sold 2,015 Tundra trucks. The government data also shows customers bought a wide range of new vehicles, from BMW sedans to Chevrolet Camaros.

Transportation Department officials have noted Cash for Clunkers achieved a 60 percent improvement in fuel efficiency because of the trade-ins. Transportation Secretary Ray Lahood told car dealers last week that the program "helped consumers ditch costly gas-guzzlers for safer, more fuel-efficient vehicles that are much better for the environment."