Critical L36 Upper Intake Manifold Info....for 2000+ owners
 

Maybe you thought like I did that the problem ended in 1999. That was either a rumor or a false hope.

I have in my lap the AC Delco UIM off of EK98's car. His is obviously a 98, but his upper (second one on the car) was manufactured on:

March 2nd, 2002 <<<<<<remember this date while you look at the EGR passage in the pics below:

Attachment 59071

Attachment 59072

Attachment 59073

I firmly believe it's only a matter of time before we start seeing more NEWER cars, particularly 2000 and newer begin to fail. Be VERY watchful of your idle quality, smell of the exhaust, and coolant levels.

Bill...This may be one to toss into the 00+ mechanical area with a link..

I understand you put it here for better exposure. ;)

I put it here because it relates to 1995-2005 (and even newer GP's, not to mention the various Buick and Olds owners here).

Bill, are we positive that is a replacement ACDelco part?

It is an AC Delco. Identical to every production L36.

Delco manufactured in 2002.

Dumb question, but does the Shortstar (3.6 V6) have this problem as well?

I have 30k on my Dorman on the '96 SE and so far so good.

Not that we know of. But, we don't follow that engine as closely as we do the Bonneville power plants.

This doesn't surprise me in the slightest. The replacement manifolds made after 2000 don't have any more real protection than the originals, unless you consider a little heavier plastic material around the coolant passages sufficient.

As far as I know, there was no better EGR standpipe protection provided.

That is why I took the opportunity to stock a replacement UIM while I could get a good deal and have the time to properly shield the passages from the EGR pipe. This even though my UIM replacement by dealer was done in 2004 with a 2004 vintage UIM.

My uim was manufactured like in 2003 went out 3 months ago fixed with a one that is supposted to stop this problem.

Ive done a pretty fair amount of research on the 3.5 and I dont know of any problems with the UIM or LIM gaskets, or any common engine problems at all for that matter.

It does have the same composite UIM though, but the problem with the 3.8 is a design flaw, not because its made of composite material.