U.S. officials yesterday, clarifying Defense Secretary Caspar W. Weinberger's account of the latest clash between Soviet and American military intelligence officers in East Germany, performed an increasingly common ritual: explaining what the secretary "really meant."

Weinberger, a lawyer, argues for a strong U.S. defense against the Soviet menace as if appealing to an uncertain jury and often leaves it to aides to refine his points later.

Refinements or retreats have followed recent Weinberger statements on such diverse topics as the future of the controversial MX missile, Salvadoran army retaliation against leftist rebels who killed U.S. Marines, and Soviet culpability in scraps with the U.S. Military Liaison officers in East Germany.

"Cap never wants to appear like he doesn't know everything on a subject, even if he's wrong," said a veteran of Weinberger's Pentagon.

Another Pentagon official praised Weinberger's accessibility, which he believes mitigates "the secretary's habit of putting his foot in his mouth."

In a television appearance Sunday, Weinberger said Soviet troops in East Germany had "deliberately" bumped a U.S. vehicle on duty there, pushed an American serviceman and held him and another officer at gunpoint, detaining them for about nine hours.

The Soviet troops, Weinberger charged, "behaved in the same way" as the Soviet sentry who shot and killed U.S. Army Maj. Arthur D. Nicholson Jr. on March 24 during a routine surveillance patrol in East Germany. Despite a U.S. protest of the latest incident, the secretary said, Soviet authorities have not responded with "anything very positive."

By Monday, Defense and State Department officials began to soften the account. There was no indication that the Soviet troops intentionally hit the U.S. vehicle, they said, although a Pentagon spokesman said they deliberately tried to block it. Nor was there confirmation that the U.S. serviceman was pushed.

According to the State Department, the U.S. vehicle was "grazed." Soviet troops "unslung" their rifles but did not point them at the U.S. soldiers, officials said. The Pentagon, however, said a Soviet soldier directed his rifle at an American.

While there has been no formal Soviet apology, Pentagon and State Department officials said a Soviet military officer called the U.S. mission to report the incident and plans to return the vehicle.

Pentagon spokesman Robert Sims said yesterday that Weinberger "just told it the way he remembered it." But another defense official said the secretary's television presentation typifies his penchant "to . . . let his staff pick up the pieces."

After a similar incident in East Germany two months ago a Pentagon spokesman suggested that a Soviet truck purposely rammed a U.S. Army vehicle. He said the secretary was "very concerned" and wanted the Soviets to "conduct themselves in such a way as not to lead to these incidents."

A week later, the spokesman said "the incident may not have been intentional."

Weinberger's aides also stepped in after Weinberger said in a radio interview July 31 that the Salvadoran army "with our assistance has taken care of, in one way or another, taken prisoner or killed . . . a number of the people who participated in that killing" of four U.S. Marines who were gunned down by leftist guerrillas at a downtown San Salvador cafe in June.

Aides said Weinberger did not mean that the triggermen had been killed or captured but was referring to members of the leftist organization that had claimed responsibility for the slayings.

Moreover, aides said, the Salvadoran attack against the rebels was mounted as part of the military's normal antiguerrilla operations, not at the request of the United States. Only routine U.S. intelligence assistance was rendered, they said.

On the MX missile, Weinberger told reporters Aug. 8 that the Pentagon would recommend new basing modes for the weapon to skirt the congressional cap limiting deployment in existing Minuteman silos to 50.

Faced with congressional criticism, however, the secretary said the Pentagon would content itself with studying alternative basing modes until fiscal 1988.