Coolant Leak

[ekordas]

I have a 2002 Yukon XL 5.3 and I've been having a coolant leak the past few months. My water pump was replaced about 40,000 miles ago and doesn't seem to be leaking from that same area. Although I've heard stories about the gasket going slightly bad and the coolant just runs down the block and drips from the rear end of the block making you think that's where the leak is coming from. Anyways I'm going through a gallon of coolant every thousand miles or so. It's all over my garage floor, originating from the mid to rear end of the block. I've gotten it pressure tested several times to try to find the leak but no such luck. It seems like the leak might be coming out faster so maybe it'll show up with a pressure test now. But just looking for some advice from you guys. Appreciate anything you come up with.

 

[DND]

I think it is probably your water pump leaking there is a pee hole on each side of the impeller shaft and it might be leaking out of the other side than your previous pump was leaking. My factory pump lasted 120000 mi. the replacement pump only lasted 35000 and it too looked like it was leaking from a different area than my previous pump. Check all your hoses etc. as well.

 

[ekordas]

Turns out we didn't know the water pump mounting bolts were not blind holes. So coolant would leak through the bolt holes. Put thread sealer on them, replaced all the gaskets, and keeping my fingers crossed.

 

[tahoe7689]

Hope that fixes it, like DND said, my original one lasted over 100K but the replacement one lasted maybe 40K, and it leaked from the little drain hole, the mechanic said weep hole or something....