The sales figures from Detroit were distorted by comparison with last year, when a strike crippled Ford's production.

Ford car sales were up 5.4 per cent to 255.431 or 1 per cent below Ford's best month ever. Adding truck sales which include vans and pickups - Ford had its best sales month ever, said Bennett Bidwell, vice president for a sales.

General Motors said its dealers sold 437,428 cars and 134,158 trucks, for a 621,586 total that was 9 per cent ahead of last year.

"Passenger car sales were up 10.3 per cent from last October and represented the best October since 1972, the best October ever, said Robert D. Burger, GM's vice president for marketing.

Total GM sales for the year so far of 4,383,174 cars and 1,250,828 trucks are running 10 per cent ahead of 1976.

Chrysler Corp. had an 11 per cent sales gain in October to 113,568 cars. But year-to-date figures were off 4 per cent to 1,062,122.

American Motors Corp's monthly sales were off 30.7 per cent to 15,235 units, and its year-to-date results are 24 per cent behind at 156,819 units.

Sales of imported cars during October totaled 143,000 units, 3 per cent more than the previous year, but the imports' share of the market fell below 14 per cent. Imports traditionally post a lower market share in October, when new American cars are introduced, but this year's decrease was sharper than usual.

Other reports from major retailers:

J. C. Penney Co. said sales were up 13.1 per cent to $762 million and year-to-date sales gained 9.4 per cent to $5.21 billion.

Montgomery Ward sales increased by 10.4 per cent for the month to $353.6 million. For the 39 weeks, sales were up 13.2 per cent to $3.18 billion.

F. W. Woolworth reported October volume up 8.4 per cent ahead of last year.

May Department Storts - parented The Hecht Co. - had an 11 per cent gain to $183.9 million for the month and an 3 per cent yearly sales increase to $1.51 billion.

Carter Hawley Hale Stores - which owns Neiman-Marcus - reported October sales of $111.1 million, up 12 per cent, and nine-month results of $977.5 million, up 8.1 per cent.