The problem is not the gasket, but the plate itself. The thin sheet steel plate expands and contracts at different rates than the aluminum intake manifold, causing gasket failure, just the same way that it always used to happen on early aluminum head/ iron block engines up until the MLS head gasket was finally mastered.

That is why no matter which plenum repair kit you get (Hughes, eBay, etc), it is going to come with a thicker aluminum plate, and not a steel one.

The method for determining whether or not the plenum has been correctly repaired is to open the throttle plates with the air cleaner off, and touch the plenum plate with an extendable magnet to see if it stick or not. If it doesn't stick, you are in luck, and if it does, you are not out of the woods.

https://dodgeforum.com/forum/2nd-gen...um-thread.html

 

Well, after reading the thread you cited, I had none of the oil or symptoms described.

I remember saying to myself when I took the plenum lower plate off, "Man I didn't have to do this one." The lower gasket was perfect and there was no leaking. It has sealed so tight that I had to scrape it off.

I went ahead and replaced it anyway. I do have to note, this job looks to be 1/2 as hard on the v6 as it is on the v8. I didn't have to remove the shroud, fan and related parts. All I had to do in the front was remove the altenator, unbolt the AC compress and move it forward, and unbolt the mounting bracket and turn it counter clockwise.

The van is running really good! It is still a happy van