I've got a 2001 2wd gmc jimmy sle with 170k miles . Blew my lower intake gasket and lost coolant , didn't overheat. I just got done replacing the lower Intake gasket , some hoses ,and sensors . As I was pouring water into my radiator to start doing a flush I noticed water dripping out of my oil plug . I'm very desperate to an answer especially since when I started this project there was no oil in the coolant .

 

If there's no damage from overheating (cracks, blown head gaskets, etc.) and there was no water in the oil before you replaced the gaskets, the only logical explanation is that you messed something up when you did the gaskets. If they didn't seal correctly, they can leak coolant under the intake manifold, which will drain down into the pan.

 

That's exactly what I was thinking . I just wanted to make sure before I tear it all back apart .
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