DETROIT, OCT. 14 -- Early October domestic car sales fell 39 percent compared with the same period a year ago, the nation's auto makers reported today.

Light truck sales also declined, off 21.6 percent from Oct. 1-10 a year ago.

Together, domestic car and truck sales fell 33.6 percent compared with a year ago -- 238,707 domestic cars and trucks this year versus 359,425 sold a year ago.

Domestic car sales, which moved at a low 4.8 million seasonally adjusted annual rate, totaled 151,043 in the nine selling days in the current period, compared with 247,623 a year ago.

The problem auto makers face this year is their success last year in luring buyers with unprecedented incentives including loan rates as low as 2.9 percent.

This year, even with loan rates as low as 1.9 percent on two-year loans, auto makers haven't enjoyed the same response to their incentive campaigns. In addition, most programs this year ended Sept. 30, while last year's major campaigns ran through Oct. 8.

"We were expecting low sales for the month of October. It clearly points out that the consumer needs incentives to get them out there, or people are just going to stay away from showrooms," said Michael Luckey, industry analyst with Shearson Lehman Brothers in New York.

"The selling rate's not going to stay {that low} very long. Inventories are piling up very quickly at Chrysler and GM. You'll see incentives out there pretty soon -- maybe in a couple of weeks," Luckey predicted.

Luckey also said sales were higher than expected at the end of September, which may have eaten into early October sales. He noted that buyers might be rebelling against a pricing system that makes options standard while sharply increasing the base sticker price.

Industry-leader General Motors Corp.'s domestic car sales dropped 43.8 percent; Ford Motor Co.'s were off 36 percent and Chrysler Corp.'s were down 41.2 percent against the year-ago mark

Chrysler suffered the smallest comparison drop in light truck sales. Chrysler's sales, which include the former American Motors Corp. Jeep sales, fell 1.4 percent from a year ago.

GM's truck sales were off 25.5 percent and Ford's sales were off 28.1 percent against last year's high-water mark.

But except for Volkswagen, foreign auto companies building cars and trucks in the United States continued unaffected by comparison with last year. While Volkswagen's car sales were off 38.5 percent -- about even with its performance throughout the year, Honda's were up 30.4 percent and Nissan's 33.7 percent.

Toyota began building cars in the United States last October and had not sold any by this time last year.

Nissan's truck sales also were up 31.8 percent against last year.