Ford Motor Co., amid reports of lagging output throughout the auto industry, said yesterday it will make major cuts in car and truck production next week idling 10,500 workers.

Meanwhile, the United Auto Workers Union told Ford the company had until midnight Thursday to settle with the union before a strike.

By Monday, the UAW will have ratified a tentative agreement with General Motors Corp., and Ford will be expected to do equally well by the union. Ford employs 190,000 UAW members, of which 2,500 were on indefinite layoff before the cutback announcement yesterday.

While five trade journals reported sagging car and truck production this week and predicted 1979 will be the lowest production year since 1976, Ford scheduled cutbacks at one Canadian and six U.S. plants "to help balance dealer inventory."

The Atlanta, Louisville and Oakville, Ontario plants, where Ford builds the full-sized Ford LTD, the St. Louis plant which builds the Mercury Marquis, and the Wayne plant, which builds the Ford Granada, Mercury Monarch and Lincoln Versailles, will halt production on those models.

In other automotive news:

American Motors Corp. yesterday priced its 1980 model cars and Jeeps an average of $111 or 1.5 percent above final 1979 prices.

In California Toyota Motor Sales U.S.A., the importer of Toyotas, said its new models would cost an average of $145 or 2.5 percent more.

The EAW central bargaining committee voted not to extend its contract with the Caterpillar Tractor Co., clearing the way for a strike against the nation's largest maker of construction machinery at midnight Sunday.