I have a 97 4runner completely stock 3.4 6 cylinder. I've checked the oil and its not milky. It has a constant steam and uses water when the outside temperature is 60 degrees or below. Ive racked my brain trying to figure it out and can't find anything mixing. Any suggestions on what the problem could be or something that I could check?

 

Have you pressure tested the cooling system.

If it is losing coolant and it is going out the exhaust you have a either a bad intake gasket or a head gasket .

If you have a leak in the heater core you would smell the coolant in the cab:jessica::jessica: