SAN FRANCISCO (AFX) - Ford Motor said Thursday it rode demand for cars like the new Mustang to a 6% increase in August U.S. sales, but with gas prices surging across the country, demand for its SUV lineup plunged.

Ford sold a total of 288,429 cars and trucks in the month. But hulking SUVs, like the Ford Explorer and Expedition, saw sales fall 33%.

"There's no question that demand for traditional sport utility vehicles has been affected by rising gas prices as well as significant changes in buyer demographics and product offerings," said Ford sales executive Steve Lyons.?

Instead, car shoppers opted for more fuel-efficient cars and crossover utility vehicles, built on a car-like platforms, which soared 52%.

The best-selling F-Series pickup, however, managed to post another record with a 6.3% increase to 90,388.

Ford shares fell 2.5% to $9.72 following the release.

Separately, DaimlerChrysler reported a 5% increase in August U.S. sales to 206,352 vehicles, with the luxury Mercedes-Benz side turning in a 7% rise to 19,267.

The Chrysler Group, which is made up of Chrysler, Dodge and Jeep brands, sold 187,085 cars and trucks, up 5% from a year ago.

DaimlerChrysler was down almost 1% to $51.28 at last check.

General Motors , with its shares down 1.6% at $33.63, will deliver its results later this afternoon.

Overall, analysts polled by Thomson First Call are expecting a sales rate of 17.2 million vehicles, up from 16.5 million a year ago but down from almost 21 million in July.

Porsche sells more cars, less SUVs

Porsche Cars North America posted a 7% increase in August U.S. sales to 2,735 vehicles.

Boxster sales jumped from 236 cars to 629 and the flagship 911 model sold 1,004 cars, up from 870 a year ago. Porsche's Cayenne SUV, however, saw its sales fall off 25% to 1,071 vehicles.

In August 2004, the Cayenne made up more than half of Porsche's overall sales, but, like at Ford, consumers shied away from the SUV given the rise in gas prices.

Elsewhere, Audi of America reported a 6.8% increase in August U.S. sales to 6,911 vehicles, paced by strong sales of the A4 and A6 sedans, which rose 11.1% and 18.5%, respectively, from a year ago.

Nissan sales up 10%

Nissan North America posted a 10.6% increase in sales to 92,365 vehicles, bolstered by strong demand for sedans like the Nissan Altima and the Infiniti M.

Nissan-brand sales jumped 11.5% to 80,026 cars and trucks while the luxury Infiniti side rose 5.1% to 12,339 units.

On the truck side, Armada and Titan showed declines while the Pathfinder turned in sales of 6,396, up from 2,498 a year ago.

Nissan Motors shares fared better than most in the auto sector in afternoon trading, down 7 cents at $21.07.

Incentives slip

Automakers spent $2,655 per vehicle on incentives in August, down 2.4% from a year ago and off 10.9% from the prior month, according to car research Website Edmunds.com.

Ford led the way with $3,799 in incentives per vehicle. GM's Cadillac topped all brands with $6,227 in promotional discounting.

Japanese carmakers upped their spending to a record $1,252 as their U.S. competition continued to ride the success of employee pricing plans.

This story was supplied by MarketWatch. For further information see www.marketwatch.com.