oil/sludge in radiator

[pressurerat]

2000 Grand prix, 3100 engine. There is brown sludge in the coolant/antifreeze. I have seen this happen when an oil cooler line failed and leaked into the radiator. This car apparently has no engine oil cooler, at least not that I see. It looks like oil mixed in with the a/f. The car was converted to green a/f about 6 mos ago and ALL the dexcool was flushed out. Head gasket? I know the lower intake needs to be replaced but can this cause oil to get in the water?????

[Chameleon-kat]

Yes it can, I would get it fixed asap, af could very well be getting into oil as well. It most likely IS the intake gaskets

[Ridenour]

Yep. LIM gasket leam is very common problem - specially amongst us Grand Am owner, but you GP owners end up having the same problem sometimes. Like chameleon said, get it fixed ASAP - That coolant will eat away at your engine bearings and you'll end up ruining your engine.

Coolant in oil = bad

God damn the LIM - specially on the 3.4

[pressurerat]

I know the LIM gasket has failed and is visibly leaking to the outside of the engine....but there is no water/coolant in the oil, under oil cap, pcv ,etc...no sign of coolant in oil. I will tear into it tomorrow to see what I find. For now, there is only oil sludge in the rad./ res., I just wanted to make sure this is not a head gasket issue. For the record there is no overheating, no steam from the exhaust, no foam in the radiator, no water in the oil. None of the classic HG symptoms.

[cjgrandprix]

Originally Posted by pressurerat

2000 Grand prix, 3100 engine. There is brown sludge in the coolant/antifreeze. I have seen this happen when an oil cooler line failed and leaked into the radiator. This car apparently has no engine oil cooler, at least not that I see. It looks like oil mixed in with the a/f. The car was converted to green a/f about 6 mos ago and ALL the dexcool was flushed out. Head gasket? I know the lower intake needs to be replaced but can this cause oil to get in the water?????

GM doesnt pu any threadlock on the bolts to that intake gasket. Eventually the bolts come loose and antifreeze/oil mix. The intake gasket can only be torqued once, then it is suppose to be replaced. A new one costs 50 bucks at the dealer.

It could also be a failed head gasket, but by the time you get to the intake gasket you are more than half way to the head gasket.

Good Luck,

CJ