Last month I noticed some coolant leak, took it in it needed a new radiator as it was worse than I thought. They replaced the radiator and thermostat and things looked good for a week, then noticed smaller amounts of coolant, took it back in and another part replaced. Driving noticed still having heat issues and radiator fan sounds like an Aircraft. opened it up looks like coolant if flushing back into backup tank from radiator.
Talking to a couple folks, this could be a head gasket which apparently is a huge deal and it was mentioned an engine replacement might be cheaper. That to replace the head gasket you have to strip down the entire engine. Any experience on head gasket replacement vs engine???
I might add my Rav is currently in a shop having the engine replaced....
Look into replacing the oil cooler on the top of the block while they have it pulled apart. Dorman an makes an all-aluminum one that replaces the mostly plastic one that notoriously leaks either coolant or oil or both. They also make an aluminum crossover where the thermostat sits (again replacing the factory plastic). Also if replacing the radiator also look at the all-aluminum replacements.
As you can tell, I've been looking into the cooling system myself. I'm replacing all those parts along with new silicone hoses, a new heating unit (one of the reasons for mine is the heater core has issues). Also replacing the over flow with a two qt aluminum and converting to waterless coolant (will just be having to flush the block as every other part of the system with be new).
