Should Replace Both Manifold Gaskets at Same Time?
Should Replace Both Manifold Gaskets at Same Time?
My mechanic informed I need to replace my lower intake manifold gasket. Assuming the upper intake manifold gasket will eventually fail, how much labor would I save if I had him replace both at the same time versus replacing them on two separate occasions?
Since the lower intake manifold gasket needs replaced, should I assume the upper will fail sooner or later? I plan on keeping the car for another 5-6 years.
The motor is Jasper crate motor I had installed a couple of years ago. The motor has at most 70k miles on it. I'm annoyed to say the least.
Since the lower intake manifold gasket needs replaced, should I assume the upper will fail sooner or later? I plan on keeping the car for another 5-6 years.
The motor is Jasper crate motor I had installed a couple of years ago. The motor has at most 70k miles on it. I'm annoyed to say the least.
2002 Ssei- 180,000 mi
2006 Cadillac STS AWD
1992 SE - 214,000 mi - Traded 12/2009
2006 Cadillac STS AWD
1992 SE - 214,000 mi - Traded 12/2009
- nos4blood70
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Re: Should Replace Both Manifold Gaskets at Same Time?
Replace everything. Replace both the LIM gaskets and the UIM with their respective updated designs. My motor just seized because I had only done the gaskets and not the UIM.
EDIT: My bad. I thought you had an L36. Replace both the LIM gaskets and the supercharger gasket and you should be fine.
EDIT: My bad. I thought you had an L36. Replace both the LIM gaskets and the supercharger gasket and you should be fine.
Re: Should Replace Both Manifold Gaskets at Same Time?
OK, thanks.
Regarding the UIM, how long can I expect before it fails (I realize that question is tough to answer).
Regarding the UIM, how long can I expect before it fails (I realize that question is tough to answer).
2002 Ssei- 180,000 mi
2006 Cadillac STS AWD
1992 SE - 214,000 mi - Traded 12/2009
2006 Cadillac STS AWD
1992 SE - 214,000 mi - Traded 12/2009
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Re: Should Replace Both Manifold Gaskets at Same Time?
The supercharger is the UIM on your car, and it can't fail the way a non supercharged (L36) UIM can fail. Sometimes the bearings in the nose of the s/c can go bad. Although its probably a good idea to change out the supercharger oil.

-Ryan
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04 GTP comp G.... December 2015 COTM........GONE
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Re: Should Replace Both Manifold Gaskets at Same Time?
I'm not sure you can even replace the LIM gaskets without seperating the SC from the LIM. And if your mechanic reused the "UIM" gasket, he needs to be fired. If he tries to charge you for a seperate job to replace the gasket, he needs to be fired.

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Re: Should Replace Both Manifold Gaskets at Same Time?
You could remove both as one, but it'd be a PITA.
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Re: Should Replace Both Manifold Gaskets at Same Time?
the LIM comes with the UIM gaskets usually. just replace both of them. get the NEW design aluminum gaksets not the plastic ones like original had.
Shane "RedZMonte"
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2004 Z16 Z06: Virgin
2000 SSEi: Kenwood DDX512, 3.25" MPS, ZZP DP, PLog, Puck Mount, NGK TR7's, DHP Tuned
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Re: Should Replace Both Manifold Gaskets at Same Time?
You'd need some pretty fancy tools to be able to remove the LIM bolts with the SC in place.00Beast wrote:
You could remove both as one, but it'd be a PITA.
Andrew - owner/operator of Bonnevilles Unlimited

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2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
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Re: Should Replace Both Manifold Gaskets at Same Time?
redzmonte wrote:the LIM comes with the UIM gaskets usually. just replace both of them. get the NEW design aluminum gaksets not the plastic ones like original had.
He doesnt have a UIM.





