3.1L coolant usage/brown sludge in overflow

[pitbull76]

Our 2002 Grand Prix is using a bit of coolant and has some sludge in the overflow. There is also some slight leakage from what I think is the intake manifold gasket. I am aware that these engines are notorious for leaking through that gasket. Has anyone had any luck getting some/all of the repair covered by GM if your vehicle was out of warranty? We don't even have 36K on ours but the warranty expired 4 months ago. Our extended warranty is worthless as well since I looked over the fine print and gaskets/seals are excluded

[GTP Dad]

The sludge in the coolant tank is a byproduct of Dexcool. It is harmless and can be cleaned out by removing the tank and flushing it. As for the intake gaskets, where exactly are you seeing the coolant? The 3.8's are notorious for gasket leaks but not the 3.1's. Check the area and get back to the forum with the results. A picture of the location would be quite helpful. As for your question some dealers will cover the car even if you are out of the mileage window but it is less than the 3 years. Depends on the dealer.

[pitbull76]

I don't know about the 3.8, but I have read in numerous places online that the intake gasket leak is common with the 3.1/3.4L V-6 engines. GM even issued a TSB for 96-03 vehicles with that engine. Maybe that isn't what I'm seeing, but I'll find out soon enough.

[BNaylor]

Originally Posted by pitbull76

I don't know about the 3.8, but I have read in numerous places online that the intake gasket leak is common with the 3.1/3.4L V-6 engines. GM even issued a TSB for 96-03 vehicles with that engine. Maybe that isn't what I'm seeing, but I'll find out soon enough.

I believe the GM Technical Service Bulletin number is (TSB 03-06-01-010) but it only covers the intake gasket under warranty. Not sure about the 3.1 in the GP but it defintely covers the 3.4 in all other GM vehicles.



Thrasher CAI, DHP v1.0 PCM,
3.25 SC pulley, CAIT GMAF, Hi-Flow CAT,
u-bend delete, 160 TS, TB spacer,
MSD 8.5mm wires, Autolite 104 Spark Plugs,
Goodyear Gatorback Serp. & SC Belt,
Nitto NT555R Drag Radials

[jimmytroanoke]

These engines are famous for that problem. GM has issued a redesigned intake gasket for them and also recommends new bolts. Just clean the old ones and loctite them. The torque is very low on them hence the need to threadlock them. If you get lucky they only leaked to the outside. Don't wait until they turn your oil into a milkshake. Then its motor time.

[pitbull76]

Originally Posted by jimmytroanoke

These engines are famous for that problem. GM has issued a redesigned intake gasket for them and also recommends new bolts. Just clean the old ones and loctite them. The torque is very low on them hence the need to threadlock them. If you get lucky they only leaked to the outside. Don't wait until they turn your oil into a milkshake. Then its motor time.

Thankfully I check this stuff regularly. The wife doesn't and it woulda been bad if I hadn't looked the other day. So far, the oil is normal; no milkiness or sludge on the fill cap. We have an appointment with the dealer on Thrusday, so we'll see what they say but there's a reddish-brown stain on the intake gasket so I suspect that's where the coolant's going. If the dealer/GM won't offer any assistance, I may do the work myself; I am pretty handy and have done plenty of work on my motorcycle, including cracking the engine case and replacing the trans, so I should be able to handle this.

[BNaylor]

Originally Posted by jimmytroanoke

These engines are famous for that problem. GM has issued a redesigned intake gasket for them and also recommends new bolts. Just clean the old ones and loctite them. The torque is very low on them hence the need to threadlock them. If you get lucky they only leaked to the outside. Don't wait until they turn your oil into a milkshake. Then its motor time.

Tell me about JimmyT. Had the intake gasket per the TSB changed in my son's '02 Alero GL2 3.4L 2K miles before the bumper to bumper warranty expired. Lucked out. No problems since.



Thrasher CAI, DHP v1.0 PCM,
3.25 SC pulley, CAIT GMAF, Hi-Flow CAT,
u-bend delete, 160 TS, TB spacer,
MSD 8.5mm wires, Autolite 104 Spark Plugs,
Goodyear Gatorback Serp. & SC Belt,
Nitto NT555R Drag Radials

[pitbull76]

Well, just got a call from the dealer. It is the intake gasket (big suprise), and guess what.... the extended warranty we bought FROM THIS DEALER is no good since the company is bankrupt. I voiced my displeasure with the situation politely and am currently waiting for a call back to see if the dealer or GM will assist us with any of the cost.

[pitbull76]

Well, after all this the dealer and GM are making good on the issue. Pretty well covering the whole thing. Now we're still a bit pissed about the warranty, but being firm and polite got the dealership to help us out on the gasket.

[richtazz]

that's great that the dealer is taking care of you. After all, you gave them your money for the warranty, it's not your fault their warranty company went belly up. This is a VERY common problem on all 96-up GM 60 degree V-6's and should be covered under a recall, but GM has REALLY good lawyers. LEt your friends know about the dealer taking care of you, sounds like a dealer I'd want to give my business to.