Teamsters union truck drivers who deliver most of the nation's new automobiles have overwhelmingly rejected a nationwide contract providing wage and other concessions and supported by Teamsters President Jackie Presser, union officials said yesterday.

The rejection by approximately 21,000 drivers and support personnel is only the second time in the union's history that members have turned down a national trucking contract proposed by union leaders.

Under Teamsters bylaws, a contract proposed by union leadership can be rejected only by a two-thirds vote of the membership. Union sources estimated the negative vote at 80 percent, but totals of the mail-ballot vote were not announced.

No strike was immediately planned, the union said.

"There will be no disruption of work, as our members will continue under an indefinite extension of the present contract," Teamsters Vice President Walter Shea said.

The Teamsters are to resume bargaining Wednesday with the National Automobile Transporters Association, representing 35 trucking firms that carry cars from automobile plants, rail depots and seaports.

Drivers turned down the proposed three-year contract because they did not believe that many concessions demanded by the companies were justified, according to Kenneth Paff, spokesman for Teamsters for a Democratic Union, a Detroit-based dissident group that lobbied against approval.

Most drivers earn 65 cents per mile while delivering cars and would have received a 3.5-cent yearly increase. Average hourly pay under the contract is about $13.

But a new concession proposed by the companies cut the mileage rate in half for return trips, officials said, which would have cut pay substantially for many drivers. Other proposed concessions included lower wages for new hires and reductions in cost-of-living allowances.

The industry considers the concessions important because of increasing competition both from railroads and nonunion trucking companies, said James Osmer, a spokesman for the Michigan-based trucking association. More than half the nation's new cars are carried by rail on at least part of their delivery routes, he said.

"This is the second major defeat for Jackie," Paff said, referring to the 1983 rejection of Presser's proposed nationwide trucking agreement that also included concessions. In letters and leaflets, Presser had pushed for passage of the new contract as a means of preserving jobs.

Teamsters spokesman Duke Zeller said union leaders were "surprised" by the vote but determined to improve the contract in the renegotiations.