How does motor oil cool a car engine?

Answer 1The oil doesn't really cool the engine. It reduces friction which means there is less heat but the coolant and radiator is what cools the engine. Answer 2, Another OpinionI have to disagree with answer one regarding engine cooling. I agree it is intended to reduce friction, BUT it does pick up a great deal of heat, which has to be removed to protect the oil from breakdown.

Some engines actually have a separate oil cooler [I'm not talking about the transmission oil cooler] for cooling the crankcase oil. and some, like the Jaguar, have heavy cast aluminum oil pans with fins, designed to dissipate heat from the oil.

I agree that the radiator system is designed for and does the bulk of the cooling, but the motor oil circulation system does contribute by distributing and disipating some of the heat.j3h.