Thanks

Guess some of the newer ones can have the intake gasket problem- talked to my dad and he had to do one just the other day at work (GM dealership), he also said GM just redesiged the gasket because of it. (the one he did was a S10 with the 4.3)

I had had a 97 sonoma and a 96 blazer with the 4.3 v6. I had to do the lower intake manifold gaskets on both of them because of leaking. Also my sisters 99 blazer had to have them done for the same reason. The dex cool coolant looked like mud in two of the trucks. I used prestone long life antifreeze in place of the dex cool and not had any problems since. ( 97 now has 130,000km on it from when the gaskets were changed and it has no signs of further problems.)

Flatlander

Flatlander'* experience speaks volumes. Dex is the devil, and the cause of many problems. Not just for the 3800'*.

yeah Death-Cool is garbage soon as spring hits im flushing and adding something different.

and i agree with whats been said above although i wouldn't rule out the head gasket. how much coolant has been lost? how many mies on it and like said above has it been run hot.
but will is right on as well might just as soon start tearing down the top end replace the UIM gasket and the lower but then again if you do all this and it turns out to be a head gasket wouldnt you need to start over lol gaskets would be able to be reused if torqued right but still its a afternoon project. and if you are going that far might aswell do the head Gaskets while you have it apart.

Yes, these engines did have lower manifold gasket failures just like the 3800. They used the same style plastic frame gasket. The new GM replacements are an aluminum frame style just like the new design for the 3800. Different part number than the 3800, but the same aluminum frame w/rubber bead style.