Excursion has been sitting about a week and a half. Lifted hood to unhook battery tender. Saw upper radiator hose was partially collapsed. Reached to loosen the degas cap and saw this. My initial reaction was oil in coolant, failed oil cooler. Am I wrong?

 

When I last drove the truck on July 19 the coolant was crystal clear when I got home. Took off the degas cap and looked in, barely anything floating on top of the coolant. 🤷‍♂️

 

 

What coolant are you running and what does it smell like?

 

Ford Gold changed every 25k miles, so changed about 10k miles ago. Smells like coolant, don’t smell anything else.

 

Pull some out and put into a clear glass and let settle overnight then post a few pictures.

 

It could be water in the coolant.

 

Damn, not good.

 

Fingers crossed! Lol

 

A little more info that may be pertinent-

I had replaced the oil cooler after I bought the truck in 2014. About 270k miles ago. Temp difference between coolant and oil never got over 10 degrees, unless cooling down, sometimes the coolant temp would go down a bit faster.

But it’s looking to me like a failed oil cooler, unfortunately

 

I don’t get it…came out this morning and it looks like this


Just drove it 15 miles and coolant looks perfect 🤷‍♂️

 

When I get home from the tire shop I’m going to drain the coolant and see what it looks like 🤷‍♂️

 

So, I’m guessing oil…most likely. Drove to tire shop and coolant looked perfect when I got there, no darkness in sight window. Got home, drained coolant from radiator drain, then from block. First approx 3 gallons in one container, then rest from radiator in second container. Coolant itself looks fine for the mileage. The lighting makes it look much darker in a couple pics. It’s all the same light yellow as in the 3rd pic. But in the last gallon and a half or so from radiator def some of what I believe to be oil





Here’s the last gallon and a half or so from the radiator drain but tilted to emphasize the oil clinging to the side



Truck now has fresh coolant in it…have to drive it back to tire shop tomorrow morning because the stick on weights fell off 🤦‍♂️ so we will see!

 

Have you thought about doing a flush via garden hose?

 

Yep, and I may end up doing that when I have some time. Fortunately I don’t have to drive the truck for a bit. I’m 99.9% sure it’s oil, so as of right now in my head I’m blocking off the second half of next week to take the truck apart and replace the oil cooler…just in case.