John Gavin, former U.S. ambassador to Mexico, said yesterday that "at least two" Mexican governors are "up to their elbows in the drug trade."

In the latest in a series of hearings on Mexico by a Senate Foreign Relations subcommittee, Gavin said one of the governors is known to have given "shelter, comfort, and protection" to a man he described as "the drug overlord of Mexico." Asked by Sen. Jesse Helms (R-N.C.), the subcommittee chairman, whether he was referring to the governor of Sinaloa, Gavin declined to "mention any names."

However, Gavin rebutted charges against Rodolfo Felix Valdez, the governor of Sonora, who was accused of growing marijuana by U.S. Customs Commissioner William von Raab in a hearing in mid-May. Gavin said he knows Felix Valdez personally, and knows he is innocent of involvement in drug trafficking.

Gov. Bruce Babbitt (D) of Arizona also firmly defended Felix Valdez yesterday. "The kind of personal defamation that Commissioner von Raab engaged in is a grave mistake" that has damaged relations with Mexico, Babbitt said. He called for an official retraction.

Gov. Toney Anaya (D) of New Mexico and Sen. Daniel J. Evans (R-Wash.), a member of the subcommittee, joined Babbitt in criticizing what Anaya called "Mexico-bashing" by Helms and previous witnesses at the hearings. Anaya accused Helms of bigotry, saying the criticism of Mexico was vague and unfair.

Gavin confirmed news reports that former White House aide Michael K. Deaver asked him last year to resign as ambassador. Deaver was paid $250,000 a year as a trade representative for Mexico until recently. Gavin, who said President Reagan had encouraged him to remain in Mexico City, resigned last month.

Helms questioned Gavin regarding Deaver's role in trade matters. "Doesn't it strike you as odd" that Deaver asked him to resign, Helms asked.

Gavin only acknowledged Deaver's request that he resign, saying, "I felt the call he was making was presumptuous."

Possible solutions to the Mexican debt crisis and failing economy were also proposed and debated. Babbitt said emphatically that "Mexico's burden of debt service should be halved." He said this was crucial for growth in the economy and called for structural economic reform.