After several years of vulnerability at bargaining tables and of concessions to employers, unions are now showing toughness and militancy in negotiations - a trend underscored in recent auto and coal contract settlements - and one expected to continue into 1985.
The United Automobile Workers and the United Mine Workers made significant gains in job security, a top-priority goal of both unions, and in wages when they signed tentative agreements last Friday.
The wage increases, however, were moderate compared with those in the past and in each instance averaged only about 3 percent annually over the next three years making them noninflationary increases in the judgment of economists and labor experts.
A Reagan administration economist called the settlements ''very good news, indeed.''
Sar Levitan, a labor economist at George Washington University and a labor adviser to the Democratic Party, said, ''One of the strongest unions in the country, the UAW, is making a noninflationary settlement.''
UAW negotiators, led by union president Owen Bieber, and their counterparts from GM shook hands at 2 a.m. Friday.
Mr. Bieber called the contract terms called ''historic'' even for an industry known for innovative labor agreements.
Specific details were not released immediately, but the General Motors settlement is reported to provide a $1 billion fund spread over six years that would supply assistance to displaced workers until they are rehired or retrained.
The settlement will also pay increases of 2.5 percent annually over the three-year contract term and continue cost-of-living adjustments and pension improvements to encourage early retirement that would open up jobs.
General Motors conceded that the terms are expensive, but Alfred S. Warren Jr., the company's vice-president for industrial relations, said that GM will come out of the negotiations ''in a better competitive position than we went in.''
As soon as the agreement was reached, the UAW withdrew strike authorizations at 17 plants where 92,000 workers had walked out Sept. 17 because of local or plant issues.
When authorization was withdrawn, strikers quickly packed up their picket signs and went home at all plants except one in Linden, N.J.
Tempers at that plant flared Sept. 20, resulting in the arrest of a number of pickets and the break-off ofn local bargaining talks.
The UAW negotiators will place the negotiated settlement before the unions' General Motors council of plant representatives in St. Louis on Wednesday.
Preliminary reports are that the majority are happy with the agreement.
Final acceptance of their terms will be left to GM unionists in ratification votes.
Although there are differences in contract issues between Ford and UAW, the GM terms are expected to serve as a pattern for Ford and UAW negotiators.
Those terms will also be important in future negotiations between the union and auto-parts suppliers, and manufacturers of farm and road-building equipment.
Peter J. Pestillo, a Ford vice-president, said the company will not walk in lock step when bargaining with the UAW is resumed.
Bargaining in other industries will also be affected. George Washington University's Mr. Levitan said, ''The GM settlement will encourage other unions to stay within noninflationary terms.''
While the terms at first analysis appear moderate, some economists are concerned that actual costs will be higher than first estimated and that a higher rate of inflation could be a result.
Also on Friday, negotiators for the Bituminous Coal Operators Association and the United Mine Workers (UMW) reached a tentative settlement on a new contract.
Richard Trumka, the president of the UMW, said the settlement includes straight wage increases totaling 10 percent over a 40-month contract term to a top $124.52-a-day rate in 1987, more job security, and revisions of ''certain work rules,'' including those for safety and health protection.
Bargaining had been going on quietly, but preparation had begun in the coal fields for possible selective strikes that could have quickly erupted into a nationwide coal-industry walkout.
The UMW also will place the terms of the settlement before its members on Thursday.
If the contract is ratified at that time, it will be the first agreement in the coal industry since 1964 reached without a strike against members of the Bituminous Coal Operators Association, the employers' negotiating group.