DETROIT -- The Cash for Clunkers program boosted sales at Ford, Toyota and Honda in August as consumers snapped up their fuel-efficient offerings, but rivals Chrysler and General Motors withstood another month of falling sales.

The program, which ended Aug. 24, drew hordes of buyers into showrooms by offering up to $4,500 toward new, more fuel-efficient cars and trucks.

The hefty rebates gave automakers and dealers a much-needed lift, spurring 690,114 new sales, many of them during August, at a taxpayer cost of $2.88 billion.

Combined, the results of all

automakers for the month are likely to mark the first year-over-year monthly sales gain since October 2007.

Ford sold 181,826 cars and light trucks, compared with 155,117 in August 2008, when high gas prices and growing economic uncertainty kept people away from showrooms.

Two Ford vehicles, the Focus and Escape, were among the top selling cars under the clunkers program. Sales of the Focus rose 56 percent, while those of the Escape crossover vehicle climbed 49 percent.

Toyota and Honda also posted year-over-year gains in August. Toyota sales rose 6.4 percent to 225,088, lifted by small cars like the Corolla, the best-selling clunkers vehicle.

Honda sales rose 9.9 percent to 161,439, also on the strength of fuel-efficient offerings.

Meanwhile, low supplies of fuel-efficient vehicles at Chrysler kept the automaker from benefiting more from the clunkers program, whose rebates encouraged customers to buy gas sippers in exchange for guzzlers with gas mileage of 18 mpg or less.

Chrysler sales fell 15 percent to 93,222 units. That was less than the combined sales of Hyundai and affiliate Kia, whose smaller sedans helped boost sales to a combined 100,665 for August.

Going into August, five of Chrysler's most efficient vehicles were already at low inventory levels. Those vehicles all qualified as Cash for Clunkers purchases.

To make up for the shortfalls, Chrysler is boosting production by 50,000 vehicles of most of its vehicles through the end of the year.

At General Motors, sales fell 20 percent to 245,550. GM said its inventory levels hit an all-time low of 379,000 during August.

GM vehicles like the Chevrolet Aveo subcompact, the Cobalt sedan and Equinox crossover got a lift from the clunkers program.

No GM vehicles made the closely watched list of top-10 Cash for Clunkers sales, but they had the largest market share behind Toyota.