Well, I called the dealership. She said that UIM was fine. She said the only thing that needed replacement on the upper was the gasket, as it was pretty beat up. She again stated the UIM was fine, and if it was showing problems that they would have replaced it.

I asked about the LIM, and why it was replaced. She stated that it was pitted, and heavily caked with oil and coolant under the UIM. She said that even if they kept the original LIM that if they had cleaned it, it would have cost me more than just replacing it. Plus, she showed me on the bill how they took $100 off the cost of the LIM (it was actually cheaper than gmpartsdirect.com'* price).

After all this information I asked how could an aluminum LIM be in such bad condition, while a plastic UIM be perfectly fine. She again stated it was due to the UIM and LIM gaskets leaking. She also mentioned that lately they don't have to replace the UIM that often, it is usually just the UIM gasket and LIM gasket that are the usual cause of the leaks.

So I asked say in 6 months or a year it'* leaking again, and they find the UIM is the problem, what then?. She said that I will still pay for the UIM, but they won't charge for labor...

So, I don't know. I can almost sense the bullsh*t flag waving, but what'* she'* saying seems plausible... I just don't see them not replacing something that needs to be replaced... I would assume that they would want to charge MORE and replace it, instead of not doing it and charging less...

Any thoughts? I can just call and demand that the UIM be replaced, and tell them I'm not paying for labor...

If they are willing to fix it 6 months to a year down the road with no charge for labor, why can't they do that now to ease ur mind???

Did they return the LIM to you? What authorization for repairs did you give them, and what was their estimate for repairs? Did they go over that estimate?

It is quite possible that the UIM was ok. The one I removed from my son'* '99 Grand Prix with around 100k miles was. I would like to see the LIM however. Some pitting is not unusual, but that is generally on the lower part of the LIM (between the LIM and the heads) rather than between the UIM and LIM.

Get it in writing!

Well, to be honest, I'm not all that worried about them replacing the LIM itself. She said it was pretty bad, and it was only $200 to replace. This was on Tuesday, she called me before having it be replaced. She mentioned it is not standard practice to replace the LIM, but in my case thought it to be a good idea, as it was pitting. She mentioned the replacing is cheaper than cleaning part when I called today, plus pointed out it was $100 cheaper than list price (which their list matches the list on gmpartsdirect). I'm not 110% convinced it needed replacing myself, but I'm not overly concerned that they are ripping me off. They have a good reputation with the few people I know that have gone there. It'* really the gamble I accepted when I decided to bring it in and do none of the work myself.

I am 1000x more concerned if I should have the UIM replaced. Archon, if you saw your son'* UIM was ok on his 100k mile engine, then I will take their word that mine is fine as well. I will still continue to monitor the coolant level as I have for the last 3 years. But it does comfort me to know that they can last 100k miles, and still be ok.

I just had it in my mind that once I found coolant in my oil, and had definite signs it was leaking in from the intake, that I would have the LIM gasket and the UIM replaced. No matter if one or the other was fine... Just pretty much like preventative maintenance on the part that isn't having a problem 'yet'...

I just feel like that since I didn't have the UIM replaced, that I'm lowering my changes of a successful repair. Or that the repair won't have lasting affects... That is my main concern. But, they are promising not to charge for labor if it does start leaking in the future.

This would have been a perfect opportunity for a shielded stovepipe to have been installed. If the UIM was found to be in good condition, the shielded pipe would add that extra measure of protection to keep it that way.

At least you got the new aluminum LIM gaskets.

I couldn't agree more, Bill.

But since they didn't replace it, maybe this is a good opportunity for me to replace with a shielded one myself, once I get some time. Even more so than time, but to wait until it gets warmer out...