A federal jury in Baltimore yesterday awarded a Brooklyn couple $3.75 million in damages from the Firestone Tire Co., the largest judgement ever levied against the Ohio-based manufacturer.

The lawsuit evolved from a 1976 traffic accident in which a Firestone belted bias tire exploded. The tire company, which has suffered through massive recalls and litigation involving the Firestone 500 radial tire, is studying the latest verdict to determine whether it will appeal.

Unlike the claims against the radial tire, yesterday's lawsuit involved a manufacturing defect in the individual tire, not a design problem affecting the entire line.

Attorneys for Helen and Nicholas Daskarolis argued that a seperation between layers in the tire caused it to expand and explode, causing the car accident which left Daskarolis severly brain damaged and his wife scarred.

The couple was driving on Interstate 95, about three miles south of Elkton, Md., on May 31, 1976, returning from a New York Memorial Day weekend trip to their home in Alexandria, Va. Since the accident, the couple has moved to Brooklyn, N.Y.

Mrs. Daskarolis, who was driving, lost control of the car and crossed the median strip, colliding with a car coming from the opposite direction.

During the first part of the trial, which determined who was at fault in the accident, a representative of Kevin P. Griffin of Baltimore, driver of the other car, stipulated that he would settle for an award of $32,500. Griffin died before the trial of causes unrelated to the accident.

A passenger in Griffin's car, Gail Montgomery Blystone, 26, who now lives in Oklahoma, settled with Firestone for $350,000. Blystone suffered a concussion and was hospitalized for several weeks after the accident.

The Baltimore jury Wednesday night found Firestone liable for the accident. Yesterday, they awarded the Daskarolises $3.75 million in damages.

Firestone argued that the tire was not defective and suggested the accident might have been caused by Mrs. Daskarolis. The tire was about 14 months old at the time of the accident.

A key question in the trial was what caused a gash in the tire, which was entered as evidence in the proceedings.

Attorneys for the Daskarolises claimed the gash was evidence of the manufacturing defect, while Firestone's lawyers said it was a result of the crash.

The judgment against Firestone included $2.25 million to Daskarolis for his injuries, which left him in a coma for nearly three months after the accident and resulted in repeated hospitalization and paralysis.

Mrs. Daskarolis was awarded $500,000 in compensation for facial scarring, pain and mental anguish. In addition, the jury awarded the couple $1 million for their lost of companionship.

Since the accident, the couple has accumulated more than $75,000 in medical bills for Mr. Daskarolis's treatment. The Brooklyn man who testified briefly at the outset of the trial, could not name the current president of the United States.

"There's nothing more that can be done for him, said attorney Melvin Block. "His wife administers rehabilitation." Block said Daskarolis is only dimly aware of what has happened.

According to Block, Mrs. Daskarolis said after the verdict "that all the money in the world can't compensate her and her husband, that two lives haves have been destroyed."

The couple had asked for $8 million.

The Firestone Co., the nation's second largest tire manufacturer, recalled approximately 9 million 500 steel-belted radial tires in 1978 after the federal government determined the tire had a "safety-related defect" which caused it to blow out or otherwise fail.

The tire involved in the Maryland accident is one of three types on the market -- the radials, the bias and the belted bias. Of the three, the belted bias has the smallest share of the market, which is declining as more drivers turn to radial tires.