The United Auto Workers, intensifying its psychological warfare against the General Motors Corp., yesterday targeted plants producing GM's most popular cars for strikes if a new contract is not reached by midnight Friday.

The announcement by UAW President Douglas A. Fraser appeared to preclude a nationwide shutdown of General Motors, the nation's biggest auto maker and the union's bargaining target for reaching a new three-year contract with the auto industry.

But it raised the possibility -- some say it is a probability -- that GM would counter the selective union strike with a companywide lockout of all its roughly 450,000 UAW workers across the country. Asked about a lockout last week, GM chief negotiator George B. Morris said the company was "keep[ing] all our options open."

The plants targeted by the union for possible strikers employ about 95,000 union workers and produce the company's fastest-selling, lowest-inventory vehicles, principally fuel-efficient compact and subcompact cars. In other words, the union would let GM keep producing cars that aren't selling.

The targets include 11 of the GM's 19 auto assembly plants, all of the company's 32 parts distribution depots and three separate facilities that produce trucks and buses, Cadillac cars and railroad locomotives.

Fraser's announcement of strike targets was devoid of any saber-rattling language, conforming to the generally amicable and low-key tone of the talks thus far. Industry observers -- citing the UAW's concern over the recession's impact on jobs, GM's eagerness to continue selling its popular small cars and the lack of any explosive bargaining issues -- say a strike appears less certain this year than usual. The UAW hasn't won a new contract without a strike since 1964.

Although selective strikes are not new to the auto industry, the strategy has not been used before in target bargaining for three-year industry-wide contracts. For the UAW, it has the advantage of hitting the company where it hurts the most while reducing the drain on the union's nearly $300 million strike fund -- unless it triggers a company lockout.

As expected, Fraser also ruled out a contract extension if a new agreement is not in hand, or virtually completed, by 11:59 p.m. Friday, when the union's contracts with GM, Ford and Chrysler expire.

While the union targeted specific plants for initial strike action, union officials noted that targets may shift as times goes on if a walkout occurs. A ntionwide GM strike was not ruled out entirely, they said.

GM had no immediate comment on the union's announcement.

Production and assembly plants that would be struck included those at Ypsilanti, Mich.; Tarrytown, N.Y.; Lakewood Ga.; Doraville, Ga.; Wilmington, Del.; Linden, N.J.; Lordstown, Ohio; Norwood, Ohio; Van Nuys, Calif.; Framingham, Mass.; Arlington, Texas; Detroit, Mich. (the Cadillac plant), Pontiac, Mich. (GM Truck and Coach); and LaGrange, Ill. (diesel locomotives).