[Ketch]

I just fixed the infamous intake manifold gasket leak back in December and she started leaking again this June. Thought I had screwed up. Then I notice it leaking around the intake manifold coolant fitting, like yours. I thought I'd try tightening it, but just a touch of the wrench and it broke off like it was made of fudge.

It took me three hours to chip the remaining part out of the threads down in the manifold. Even though it is metal, its non ferrous I guess and the magnet did nothing to retrieve the broken pieces that fell into the manifold.

Tommorrow I'm going to get a new part from dealer and then find a matching tap to clean out the remaining part which seems to be fused to the manifold threads.

Once I get it to where it will accept a new fitting, I will open the coolant drain bolt in the bottom of the block and run the hose through the fitting hole. Hopefully this will flush out the bits of the old fitting that fell into the manifold. Else, they'll end up destroying the water pump or lodging in the radiator.

There may be a reason why this thing deteriorated. I know its not my coolant mix. Its exactly 50/50 Dextron to distilled water into a fully flushed (including draining the block) cooling system.

Such a shame. We have just 60,000 miles on this (a 1999 Suburban LT 5.7L) and this is just one of a string of problems related to cheap materials and poor quality. I may never buy another GM product again after this. GM, I hope you are listening.