As my car is creeping up in the miles, I'm getting more and more nervous about my lovely plastic intake. I feel like I'm driving a time bomb that is waiting to go off. My car has about 62k on it. Not exactly high miles, but getting up there in the range where the intakes start having problems (as far as I know).

Is it almost a better idea to start thinking about getting it changed now while I haven't been showing signs of it being bad?

I have been watching the coolant level pretty closely over the past year or so, just to make sure I'm not losing a ton all of a sudden. I have noticed that over the past year that I've lost about half an inch in the reservoir tank, maybe a shade more. I'm not sure if that'* normal, or signs of it starting to go. Or what are signs of it starting to go?

My question is, should I just bite the bullet and take it to the shop and say hell with it? Just tell them to replace the upper intake now? If I have them do it, should I have them replace the lower intake gasket as well (since they are big problems, and they'll be pretty close to it anyways)? Or am I just getting paranoid on the issue?

I'd just prefer to have my car last a good long time yet, and would rather pay $$$ now, instead of $$$$$$$$$ later. Just looking for your guys opinions on this, and to see what you guys have done with these issues. Thanks a ton.

how many miles do you have on the car? There has not been a large percentage or 00+ with intake failures, nowhere near the extent that the pre-2000 have shown to suffer. Half an inch in six months in the resivior is NOTHING to be concerned about whatsoever

Mine actually went 120+K miles before failing, though I know that is higher than the average for the '96-99 intake failures. You have only 62K (again about average for the pre-'2000 failures), so I would suggest you just keep a good eye on things. Your car will tell you when it'* time, especially since you obviously DO keep a close eye on things.

If you were one that rarely to never opened the hood yourself, I might advise otherwise. When you do decide to do the UIM, I suggest you spend the extra and get those LIM gaskets replaced. I don't personally know how well they are holding up in the 2000+ 3.8Ls, but as far as I know the new improved GM LIM gasket didn't show up until 2005.

62K is not at the normal average replacement mileage yet. I think most see issues 80-120K. Most likely you have some time on the clock and that is good.

Doing it before it is required is the best way. Then you know water never got into the bottom end. Yes, there is no doubt in my mind after seeing an L36 with 75K on it that the lower intake gaskets should be changed. And the suggestion would be to get the lower intake gaskets from the dealer. Dealers are now stocking an aluminum frame gasket that superceded the original plastic frame gasket.

Bob Dillion is providing a good low cost sleeved UIM and the other choice to consider would be the Dorman/Motormite UIM

Alright, sounds like I'm jumping the gun a bit.

If I'm still not losing much coolant come 75k or so, I'll probably start looking into getting at least the LIM gasket replaced, and maybe the UIM depending on what they say at the shop. Plus I would definitely take it to a dealer for something major like this, as they've probably changed a 1000 of them already.

Thanks for all the info on this.

It'* actually the lower intake gaskets that degrade over time and the dex cool doesn't help. All the engines seem to have the lower intake gaskets degrade over enough time and mileage.

I changed mine at 140,000miles, while they looked bad, they weren't really leaking. There is a new aluminium frame gasket that GM superceded the old part with and we are hoping this fixes a good part of the issue.

I just had mine changed at 82K miles. It was leaking pretty badly.

Some people may argue this, but this is what steps I have taken to help hold off this problem.

1. Added a 180* T-stat.

2. I took my car to a mechanic and had them do a complete flush and fill. It flushed out the entire block as well as hoses and radiatior. And then I had them fill it with green antifreeze. I use the Prestone that runs with any color. I just said Bye Bye to the dexcool.

Maybe this helps, I hope so,

Tim

I did a coolant flush on my '99 GP and I put in a 180* tstat, but I'm pretty sure my LIM gasket is already gone. I hope its been replaced before with the miles that are on it (205k), but if not that explains why it is bad. I am going to try the new revised plenum or maybe even the L26 plenum and see if that does anything.

But with 65k I wouldn't be worried. Like was said just watch your coolant like you said you do and if it starts losing more than normal then be worried. There is no sense in replacing something that doesn't leak now because replacing it now might cause it to leak. Just my $.02 though.

Shawn