GM's Redesigned 2003+ LIM gaskets

[Rhedalert]

Has anyone heard of these redesigned gaskets failing? Anyone in a dealership see it? 40k miles since I installed mine and it looks like I have an internal coolant leak. I'll make two guesses as to what the problem is, but I won't know for sure until I tear it down. Yes I did use the replacement GM manifold bolts.

[19Cutlass94]

I bought GM gaskets for mine about 1-2yrs ago and have put ~40K on them and all seems well.

[Superdave]

i have 71K on my '04 3400 and they're starting to seap out the sides a little.

[IsaacHayes]

Yep, if they are plastic, they will warp and fail eventually. The "improvement" on them is only metal tabs that prevent it from cracking from improper installation.

Go with metal felpro! (btw my GM gasket I replaced before it showed signs of leakage but even at less than 2 years it was showing signs of separation from the plastic..)

[Rhedalert]

well in addition to the metal tabs, the seals around the coolant ports did seem thicker, beefier, and more rigid. The really old style gasket feels more flimsy there, which I thought was part of the problem. If these fail, I am SO going to use the FelPro's. I used them on my sister's '02 GP 3100 when hers failed.

I mean really, 40k life on gaskets is such crap, I was careful as hell like I always am, and still have a problem.

And it also sucks, since other than changing the oil, I had no evidence of this occuring. Oil level was fine, dipstick was clean, valve area was free of milky crap, etc. When I pulled my drain plug, the first ounce of oil was light tan. The rest checked alright. Then I saw my oil cap this morning (I did the oil change last night)



Now I know when I've been finger-licked.

[geldartb]

shit in my old 3400 from the grand am mine only lasted 10k and 1yr time give or take before it went to hell in a handbasket.

did everything the way your suppose to and bam, the funny thing though it wasnt leaking in the typical spot by the thermostat or by the power steering pump. i started out with the low coolant light an hour away from my house on my way home and quickly went downhill.
i had the moisture for a few days then the shit on the oil cap and before you know it got 10 thousand times worse, and at the bearings enough to give it a knock so i found an engine with 300 miles on it and here we sit today with me tearing it apart to put a cam in it.
the engine now has 7k on it and no signs of leakage, when i popped the lim off it was sealed tighter than a virgin, damn thing was like superglued.
i had oil in the coolant and coolant in the oil.

[Rhedalert]

Yeah, my original 3100 gasket, and my sister's '02 3100 gasket were both external, with minor seepage under the TB area. This time around it's externally bone dry.

[SappySE107]

Hold on. Is it cold there:P Do you do a lot of stop and go driving? I had the same looking shit on my oil cap and some under the valve cover on my 3.4 DOHC. My old stat was bad so it wouldn't get up to temp like it does now. Condensation could be your problem and not a coolant leak.

[IsaacHayes]

I too have heard about the cold air and moisture getting in the oil. Well each time I sealed up the gasket well I have not had ANY moisture on the oil fill cap or when draining the oil and it's been very cold here for several years. When I caught the first LIMG it was on the oil cap like that. Tore into it and the gasket was FUBAR. 2nd time it was seeping outside of the motor. 3rd time wasn't leaking yet but I did the intake swap and the gasket ports were starting to creep.

If you have some milk in the bottom of the oil pan then I'd say that's more than condensation. Like I said I had hardly any miles on the 3rd gasket and it was already showing signs that it was going to fail.

[Rhedalert]

nah this car is driven often, 80 mile round trips on the highway to work and back. I considered condensation and moisture collection but really it can't happen with that kind of driving. Engine runs at 195-202F pcm checked.

[tractorman]

If in doubt, taste it. You'll know.

[Rhedalert]

lick the oil cap like Im licking a pudding lid? NEVAR

[geldartb]

i just pulled apart my now 7k 3400 to put the cam in, it was like the gaskets were super glued in. they came out with the lim.
i had to put some effort into taking the lim off the engine. then the gaskets were like superglued to the lim.

wasnt leaking and didnt show any signs but those gaskets are history. metal ones for me this time.

kinda felt bad tearing into a good fresh and non leaking motor.

[IsaacHayes]

I did too when I did my intake swap but looking closely there was some separation from the rubber seal from the plastic. You had to look for it but it was starting.

[IanSzgatti]

the series III 3800's must have some shity gaskets too, i've seen a number of them leak...