Hi,

I'm at work with nice work clothes on, guy I work with comes over, mentions water leak on his '04 6.0 Vortec. Walked out with him, good sized puddle of Dexcool on the ground under his truck. He didn't notice anything on garage floor or driveway, may have started after he left for work this morning. Looks like it's coming from the back of the engine, dripping onto a crossmember that runs between the lower A-arms.

It has one of those plastic intakes on it, do these leak at the back corners? Any known leak areas on these trucks? It's still got a little in the bottle, so it hasn't leaked a ton yet. This guy takes good care of his stuff, it's not neglected at all but it doesn't call for a coolant change till 100K, has about 64K on it. It tows a trailer and goes out in the woods some, but no troubles at all till now.

Yeah, I know it's not a Chevelle, but WTH? Anybody got any bright ideas?

anybody on here know about these trucks? TTT

no coolant in the intake. waterpump gaskets leak, lower hose clamp brakes and cuts lower hose at pump and radiators leak

Could it be a cracked recovery tank? "Some" late Chevy cars have this trouble.

Not sure about that motor but my 96 4.3 has the plastic intake manifold, and the gasket blew out last winter. The mechanic(It was more than I could handle on a weekend and my truck wont fit in my garage) who fixed it for me refused to put dexcool back in it. He runs the fleet shop at my work, said when they buy a brand new GM truck the first thing they do is drain the dexcool and add regular green prestone anifreeze. Dexcool is notorius for gumming up and causing gasket failures. New gaskets are cheap but I think it was 6-8 hours in labor.

Dan and Jeff, can you guys reconcile your opinions? they seem to be directly opposed. This engine does have a tall plastic intake, or is it just the plenum?

There is no coolant in the intake on LS series engines, I think he will need to get on the ground and trace it up the block to narrow it down.


LK

Get rid of the Dexcool. There have been recalls on that crap. It was supposed to last 100,000 miles but I had problems after about half that. Check this out: http://www.google.com/search?hl=en&q=dexcool+problems&revid=1491108870&sa=X&oi=revisions_inline&resnum=0&ct=broad-revision&cd=4

There is a tube that connects the two heads, IIRC, that crosses the back of the block, might have sprung a leak here...Haven't heard too many leak complaints on the LS motors yet..

I would bet money it is the water pump gasket(s). As stated above there is no coolant passage in the intake. It could also be the coolant crossover gasket. Those gaskets are soft aluminum with silicone rubber inserts and they tend to seperate and leak after 100K

I would bet money it is the water pump gasket(s). As stated above there is no coolant passage in the intake. It could also be the coolant crossover gasket. Those gaskets are soft aluminum with silicone rubber inserts and they tend to seperate and leak after 100K

X2

I have had too replace that gasket on a 5.3 liter and a 6.0 liter, major PITA!!!!!