The AFL-CIO, brushing aside some earlier reservations, gave its qualified support today to the Carter administration's drive to win Senate ratification of the SALT II treaty with the Soviet Union.

In a compromise engineered by AFL-CIO Secretary-Treasurer Lane Kirkland, the federation's Executive Council said it will support the pact if the Senate commits itself to new steps "to remedy the emerging strategic imbalance and to move toward genuine strategic arms control."

The council defined its conditions as including:

Further "modernization and development of U.S. strategic forces, including, and most particularly, the MX missile based in such a mode as to survive a first strike by Soviet missiles."

Specific directives to SALT III negotiators on the goals and timetables for achieving mutual cutbacks in nuclear warheads, which the council described as the "real instruments of destruction . . . which SALT II on inclusion of these points in the Senate's advise-and-consent resolutions on the treaty, Kirkland indicated that the AFL-CIO will not necessarily oppose the pact if they are excluded.

"I'll jump off that bridge when I get to it, and I don't think I'll get to it," said Kirkland, spokesman for the council in the absence of the federation's ailing president, George Meany.

Kirkland said he expects the Senate to add even more far-reaching provisos, noting that the AFL-CIO's qualifiers do not go as far as those proposed by former secretary of state Henry A. Kissinger and several senators who are calling for major increases in overall defense appropriations in exchange for treaty support.

The council's pro-SALT vote, with only two of 35 members dissenting, marked both a turnabout and an achievement for Kirkland, who is Meany's heir apparent and the federation's specialist on defense and disarmament issues.

Only six months ago, Kirkland voiced strong misgivings about the emerging outlines of the SALT pact, descrining it as a "colossal failure to control nuclear arms." Bu the subsequntly went to work trying to fashion a compromise between the federation's hawks and doves on the issue and, when asked today what changed his mind, he responded, "Common sense."

The two dissenters were William W. Winpisinger, president of the International Association of Machinists, and Murry H. Finely, president of the Amalgamated Clothing and Textile Workers Union. Winipisinger is strongly opposed to the MX development and directives for SALT III but not making them conditions for approval of SALT II was advanced by Glen B. Watts, president of the Communications Workers of America and one of Carter's strongest labor allies. It was rejected, 22 to 7.

Kirkland reportedly opposed the Watts proposal, but later told reporters that he believes the qualified endorsement is in line with administration policy. "I do not think it is in conflict . . .I'm quite sure it is not," said Kirkland, adding that the administration has supported everything the AFL-CIO is asking, although not as part of the treatyratification resolution.

On economic matters, the council, rejecting all suggestions of a tax cut, advocated expanded jobs and training programs, standby public works projects, credit controls, export regulations and other measures to help reverse the downturn.