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99 GTP: Advice on replacing head gaskets as PM


DrRadar
10-25-2014, 11:12 AM
I'm doing comprehensive maintenance on my 99 GTP 198k miles. I've got the LIM out and a bunch of other stuff. I'm wondering if I should replace the head gaskets since I'm this far.

Their are several fluid leaks to be fixed (coolant and oil). But I've attributed to other than head gasket. But that's not to say they are definitely not leaking. I would hate to put it all together to learn there is a head gasket leak.

But I've never replaced a head gasket. How big of a job is it? The exhaust manifolds have never been unbolted; do those bolts often get so stuck that I'll create more problems trying to take them off?

So is it wise maintenance? Or leave well enough alone?

Tech II
10-25-2014, 03:08 PM
198K? Plan on keeping it for awhile? Rest of vehicle in good shape? Body? Tranny?

If yes, I would do it....remove exhaust to exhaust pipe bolts.....remove the crossover pipe.....leave exhaust manifolds on the heads.....if you see the head gasket was leaking, and want to shave the head(s), then remove the manifolds....easier removing those bolts with heads off the car anyways.....

DrRadar
10-25-2014, 03:28 PM
The rest of the car is in good shape (IMHO). I do plan on keeping it for as long as I feel like maintaining it - that's why I've done as much as I have. I will add changing the head gaskets to the plan.

Stealthee
10-26-2014, 09:15 PM
If it ain't broke don't fix it. 3800's are not known for blowing headgaskets like they are LIM's. I see no need for the extra work in doing headgaskets unless there is a known problem.

DrRadar
10-26-2014, 11:06 PM
I would do it....

If it ain't broke don't fix it. 3800's are not known for blowing headgaskets...

Since that's settled....

Well, is there a way to check the integrity of the head gaskets with the car in its current state (LIM off, water pump off, P/S pump off, etc)?

Tech II
10-27-2014, 08:29 PM
Stealthee is correct...if it ain't broke......and 3.8's are not known for head gaskets, but I have seen them replaced....

But when you get around 200K, and you plan on keeping it for awhile, then I would do it, since you are halfway there....

rkvons
10-28-2014, 11:56 AM
I'm doing comprehensive maintenance on my 99 GTP 198k miles. I've got the LIM out and a bunch of other stuff. I'm wondering if I should replace the head gaskets since I'm this far.

Their are several fluid leaks to be fixed (coolant and oil). But I've attributed to other than head gasket. But that's not to say they are definitely not leaking. I would hate to put it all together to learn there is a head gasket leak.

But I've never replaced a head gasket. How big of a job is it? The exhaust manifolds have never been unbolted; do those bolts often get so stuck that I'll create more problems trying to take them off?

So is it wise maintenance? Or leave well enough alone?

You should consider changing your Valve Guide seals. Easy to do if everything is out of the way.

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