Hi everyone! Thanks for sharing all your knowledge, I have learned alot since finding this site! I have owned a 98 Bonneville SE for about 3 months. I have 41K on the clock. I have read numerous posts about the UIM failures so I took the heat shield off my car and it appears to have been replaced on 9-04 (or at least that is the date stamped on it). My question is how do I know what brand this UIM is? Also do GM, others make an "improved" UIM that supposedly last longer?

Also I have seen people post that they have put a 180 thermostat in. What exactly is the purpose of this and should I be looking to do this?

I have not had any other problem thus far with the car and am very happy with it to this point. I just want to keep a close eye on this UIM thing. Is there anything else I should be doing or looking out for? Thanks again everyone and have a Happy New Year!! Chad

welcome to the club,
You should be OK with your intake if they also did the lower gaskets. Is there anyway to find out from the previous owner?
My 96 has been trouble free also other than routine maint.
I would check your idler pulley. The bearings tend to go dry and need to be re-lubed.

I might have to dig through some records but that is a good idea to ask the previous owner. Thanks for the input!! Chad

For the thermostat question, with a 180* or 180* drilled, the engine is kept cooler because of the thermostat "engaging" (if you will) at an earlier temp.