My 74k Miles 99 S-10 4x4 is leaking water into the oil. No overheating, runs great. I suspect (more to the point -- I hope) the problem may be a leak in the oil cooler in the radiator itself. Anyone info/advice on leaking oil coolers greatly appreciated.

And yes, the oil-cooler lines were replaced a few months and 5000 miles ago.

Thanks
Jim

 

I would check the lower intake manifold gaskets. Your truck is the right vintage to have failed gaskets. Check around the front and back of the lower intake manifold for wetness. Also check the oil to see if it looks like a chocolate malt.

 

water in your engine will damage bearings pretty quick like it did on mine...

fix it fast.

 

first advise, DONT drive it with water in the oil, and drain the oil and put fresh stuff in, but by all means, dont drive it, chances are, if you already have water in the oil, it is eating the main bearings away.

 

Yeah, the beast is put up until I get a chance to look into it more carefully. I've not done a careful examination yet. Problem was discovered during an oil change, but not by me, so I didn't actually see the evidence. Mechanic claimed the water came out first, but I don't think the vehicle hadn't sat long enough for the oil and water to separate in the pan. I'm away for a while and will investigate more carefully when I get home.

Thanks for the feedback.

 

Probably lower intake gaskets, or maybe a head gasket. I wouldn't think the oil cooler would fail in such a way as to leak water into the oil. Is there oil in your coolant?