Engine overheated 95 doing 65 mph. Is my transmission bad too? There's no evidence of anything that went bad except a crack radiator. I believe that either the water pump went bad or the thermostat but it's hard to tell without cracking everything open. It was 2 gallons of radiator fluid left. It cracked at the top where everybody else is cracked after 20 years plus. Could it have just been the radiator. Everybody keeps saying that the block should be good but if it overheated it can that warp all that good stuff down there? I really just need to know the transmission is good or not so I can at least save that. Is there a transmission cooler in my radiator 2002 Lexus GS430? Please let me know.

 

Normally the transmission doesn't care if the engine overheats. Only a very small amount of fluid goes through the internal radiator cooler at a time. Unlike the engine which is totally reliant on coolant at all times.