Oct. 3 (Bloomberg) -- General Motors Corp. and Ford Motor Co., the two biggest U.S. automakers, said U.S. sales of cars and trucks plunged in September as the lure of employee discounts faded, while the largest Asian automakers gained at least 10 percent.

GM sales fell 24 percent, and Ford dropped 19 percent, the companies said in statements today. Toyota Motor Corp., the No. 1 Asian automaker, had a 10 percent increase, No. 2 Nissan Motor Co. rose 16 percent, and Honda Motor Co. advanced 12 percent. DaimlerChrysler AG's sales of Chrysler and Mercedes-Benz vehicles were up 3.7 percent, and Hyundai Motor Co. climbed 9.1 percent.

Total U.S. sales of cars and light trucks fell 7.6 percent in September, to 1.33 million vehicles, according to Autodata Corp. Employee-price discounts at GM and Ford, which lifted sales in June and July, have lost their appeal, analysts said. Gasoline prices, boosted further after hurricanes Katrina and Rita, pinched sales of sport-utility vehicles such as the Ford Explorer, which fell 58 percent last month.

``The hangover has already started'' from employee-pricing promotions, Kevin Tynan, an Argus Research analyst in New York, said in an interview. ``You have gasoline prices at $3'' a gallon. ``It's pushing the shift to smaller, more fuel-efficient'' vehicles.

Automakers sold cars and light trucks at an annual rate of 16.4 million units in September, down from 17.5 million in September 2004, one of that year's strongest months.

Asian automakers captured 38.2 percent of the U.S. market, their highest mark for any September and their second-highest ever after August's 39 percent, according to Autodata, of Woodcliff Lake, New Jersey.

Employee Discounts

Detroit-based GM, the world's largest automaker, introduced employee prices for all customers in June after sales declined through the first five months of the year. GM posted a 47 percent increase in sales that month and a 15 percent gain in July before a 13 percent drop in August. GM's employee-discount program expired Sept. 30. Ford and Chrysler, which followed GM's offer in July, end their discounts today.

GM sold 349,202 vehicles last month, down from 458,7999 a year earlier. GM's car sales fell 14 percent, while sales of light trucks slid 30 percent. Sales of the Chevrolet Silverado pickup truck, the company's top-selling vehicle, declined 27 percent. Among GM's big SUVs, the Chevy TrailBlazer fell 24 percent and the Tahoe dropped 56 percent.

`Challenging Month'

``We had a very challenging month,'' GM sales analyst Paul Ballew said in an interview. ``We had some pockets of strength, but once again with the number of headwinds for the month, we were down.'' He noted that GM sold so many vehicles with the employee discounts that inventories have been reduced to record lows.

Ford tallied 228,157 sales, off from 282,656 a year earlier. The Dearborn, Michigan, company's truck sales fell 27 percent while car sales increased 3.3 percent. Sales of F-Series pickup trucks, the top-selling line of vehicles in the U.S., dropped 30 percent.

Explorer sales of 12,879 were the lowest monthly total since the model was introduced in March 1990, Autodata said. Ford said it set a monthly record for the gasoline-electric version of its Escape small SUV with 1,808 sold in September. Overall Escape sales fell 4.1 percent.

Sales of the Mustang sports car rose 73 percent. Ford's figures released today include import brands and heavy trucks.

Chrysler sales rose 4 percent to 175,556, capping an eighth consecutive quarter of increases, Stuttgart, Germany-based DaimlerChrysler said in a statement. Mercedes-Benz rose 0.6 percent to 17,552.

Small Is Beautiful

Asian automakers commanded a record 39 percent of the U.S. industry in August. The increases at Toyota, Nissan, Honda and Hyundai combined with the GM and Ford declines will boost that number higher in September.

Toyota raised September sales to 178,417 vehicles. The company said it was helped by demand for gasoline-electric Prius cars and hybrid Highlander and Lexus RX 400h SUVs.

Nissan sold 93,540 Nissan and Infiniti-brand vehicles, Jed Connelly, senior vice president of the Japanese automaker's U.S. unit, said in an interview. Higher fuel prices in the month appeared to boost sales of Nissan's compact Sentra cars and mid- sized Altima sedans and Murano SUVS, the company's most fuel- efficient models in their respective categories, Connelly said.

``We're trying to increase supply of those models,'' he said. Conversely, sales of the large Armada and Infiniti QX56 SUVs slowed from previous months, he said.

Crossovers Coming

``The wave of the future is the crossover SUV,'' said George Magliano, director of auto-industry research at Global Insight, a forecasting firm in Lexington, Massachusetts. ``They offer a more comfortable ride, and they get better gas mileage.''

The average U.S. price for unleaded gasoline hit a record $3.06 a gallon on Sept. 5 and the current average price is $2.94 a gallon, according to AAA's fuel-price Web site.

Honda began selling a redesigned version of its Civic small car Sept. 9. It's the most fuel-efficient version of the model to date, traveling about 30 miles per gallon of gasoline in city driving and 40 mpg on the highway. The new model helped lift Civic sales 37 percent from a year earlier to a monthly record of 30,165, Honda's U.S. unit said.

AutoData's industry-wide figures include estimates for Volkswagen AG, which didn't report U.S. sales for its Volkswagen and Audi brands today.

To contact the reporters on this story: Bill Koenig in Southfield, Michigan, at wkoenig@bloomberg.net

Last Updated: October 3, 2005 17:48 EDT