Oil in Cooling System

The trouble involved the cooling unit for the automatic transmission oil, which is placed in the car's radiator. The fittings between the cooling unit and the radiator gave no trouble when whale oil was the fluid, but the substitute allowed the fittings to corrode. That permitted the oil to get into the radiator's cooling system and the radiator's antifreeze to get into the transmission.

This damages both the radiator and the transmission, requiring a major overhaul, which normally would cost more than $400. But under an informal arrangement, G.M. says it has been paying for the work no matter what mileage was on the cars.

However, several owners in the Detroit area denied this. They said they had been forced to pay for their transmission repairs. One man, John R. Fitzgerald of suburban Livonia, said he was only able to be reimbursed after Senator Philip A. Hart, Democrat of Michigan, interceded with the company.

The normal car warranty is 12 months or 12,000 miles but Mr. Bates said that General Motors was expected soon to issue a formal policy statement to dealers telling them that any such problems on cars in the future will be covered under what amounts to an extended warranty.

Models With Problems

One automatic transmission with the problem is G.M.'s “400” series, which goes on the regular size cars. The concern produced 2.1 million of these cars in 1973–74 with the transmission. “We have had 5,000 failures, which is 0.24 per cent of the total,” Mr. Bates said.