Positive test for exhaust gas in coolant, 5 weeks ago (?), coolant loss, but not external or thru tail pipe, drain oil and found the missing coolant. Time to make room to work on this truck.

 

I just changed the oil recently and the oil looked fine, not milky or looking contaminated. it seems like every time I top it off the tank settles a the low position within a couple weeks and stays at that level. I will try to do a pressure test next weekend.

 

ebg18t,

Pressure test is a good idea, we have had guys with loose fittings under the coolant expansion tank (right under your nose, so to speak).