The Senate confirmed Malcolm M. B. Sterrett to be a member of the Interstate Commerce Commission Tuesday night, 4 1/2 months after he was nominated by President Reagan.

The action unblocks a logjam that had left the ICC, an agency that by statute may have as many as 11 members, operating in 1982 with just two members whose terms haven't expired.

The delay on the Sterrett nomination is part of a political hodgepodge involving some congressional unhappiness over the prospective political imbalance of the agency members, partisan and White House politics, internal trucking industry politics, deregulation philosophy and the questioned commitment of current ICC Chairman Reese H. Taylor Jr. to increased competition in the trucking industry.

ICC nominations also appear to comprise the single arena in which Transportation Secretary Drew Lewis, who generally wins praise for his performance in Washington, seems to have lost every battle he's fought to put deregulators on the ICC. Lewis' choice for ICC chairman had been John DePodesta, former general counsel of Conrail. Lewis then supported for ICC membership Constance L. Abrams, an ICC official, and William K. Ris, an aide of Sen. Howard W. Cannon (D-Nev.), who played an important role in the deregulatory legislation.

Lewis lost his battles within the White House--in the case of Ris, to Deputy White House Chief of Staff Michael K. Deaver, whose former clients included the California Trucking Association, which had opposed Ris.

Right now, the commission has four sitting members: the controversial chairman, a Republican whose term expires at the end of 1983; Reginald E. Gilliam Jr., a Democrat whose term expires at the end of this year; Robert C. Gresham, a Republican whose term expired at the end of last year; and Charles L. Clapp, a Republican whose term expired at the end of 1980.

Lame ducks Clapp and Gresham still serve because, under the ICC statute, a member may continue to participate in the business of the agency until actually replaced by someone nominated by the president and confirmed by the Senate.

Awaiting Senate confirmation behind Sterrett--a Republican who has been vice president and general counsel of the U.S. Railway Association--is another Republican nominated by the president at the same time: Frederic N. Andre, a consultant who would replace Clapp on the agency. Sterrett will fill a vacant seat. Both would serve through the end of 1987.

It's expected that Andre will be confirmed shortly, possibly today. One Hill source, asked whether Andre and Sterrett are considered more deregulation-minded than Chairman Taylor, replied rhetorically: "Does McDonald's have a golden arch?"

Sterrett's confirmation came shortly after Cannon, the ranking minority member of the Senate Commerce Committee, lifted his hold on the Republicans' nominations. Cannon had expressed concern primarily about the partisan makeup of the commission. Three of the four current members are Republicans and one is a Democrat. With Sterrett and Andre on--and Clapp off--there would be five members--four Republicans and one Democrat.

The heavy representation of Republicans on the ICC technically is not in violation of the Interstate Commerce Act, which requires that no more than six members from the same political party serve on the agency at the same time. But the law envisioned a full complement of 11 members, and the agency's membership hasn't exceeded seven since 1977.

Hill sources say that packing the agency with members from the president's party violates the spirit of the law and tradition. Generally, the White House nominates both Democrats and Republicans. One GOP source noted with some regret that most of President Carter's nominees to the transportation regulatory agencies were more in keeping with a proderegulation philosophy than Reagan's appointments have been.

Last month, the president also nominated J. J. Simmons III, vice president for government relations of Amerada Hess Corp. in New York, to be a member of the ICC through 1985. Simmons, a former Interior Department official, said yesterday he is a Democrat registered in Oklahoma, where he was born.

A hearing on Simmons' nomination has been scheduled for Feb. 26, and Hill sources say he can expect a grilling. Referring to some unhappiness with Taylor, one GOP source on the Hill said, "We've been burned once, and we're not going to be burned again."

Although the White House hasn't been critical publicly of the current ICC, there was some hint of unhappiness in the president's economic report released yesterday. The report extolled the virtues of deregulation of transportation and noted that the ICC had moved quickly initially to implement provisions of the 1980 trucking act, resulting in a "much more competitive" industry.

"More recently, however, the pace of regulatory reform has slowed," the report went on. Restrictions on the scope of new operating authority have increased, and the ICC has rejected some applications for rate reductions, the report said.