I got some time today while the weather has been very nice in the upper Western part of NYS. I decided that I would pull the upper intake off the car, and start working on it while the weather is nice. It took me about 45 mins to pull the upper part of the intake off. I noticed right away that the EGR passage port has a small hole in it on the throttle body side of the intake manifold. I have ordered a new upper intake manifold, and I'm waiting for it to arrive in the mail. The lower intake valley is filled with coolant, but it looks like it hasn't gotten into the oil yet. I'm in the process of cleaning the lower intake valley, and hopefully if the intake comes today via UPS, I will finish up the car this evening or sometime tomorrow.

Jay

In another thread you mention the lowers look good.

For the cost of doing it while you are there, it'* more than worth it. Another member sent me an email today that his car is sipping coolant, no leaks and not in the oil. It'* lower intake gaskets. Upper was done, but not lower gaskets.

And I'm interested, how were you able to tell the lowers looked good if you didn't pull the intake and look at them?

Looks good so far, hopefully you are enjoying the great weather we are having.

I agree...do the lowers.

My upper was replaced and once again the motor is sipping coolant. SO now I have to take appart the whole intake area just to replace the lowers, which could have been done while it was off the first time.

What year was the other members car? Was his car running the dextron coolant? The dextron coolant is highly acidic and this is why GM had problems with all the gaskets on the 96+ vehicles. I'm not talking about the intake manifolds, but the intake gaskets, ect! The lower gaskets look clean and good by looking at them. There are no signs of seepage in the lower gaskets. My 95 doesn't use the dextron coolant, but uses the regular antifreeze.

'Twas me Mine is a 96 with approx 140k (I think its 138k but whos counting!)

The car originally came with Dexcool, but according to warranty records it was switched out around 8,000 miles with the green stuff. I did have my upper done but did not do my lower gaskets yet, which I'm sure I'll be doing this winter...

Hey Bill you have a heater out in the garage? We need Roy to hook you up!

If I have problems with the car loosing coolant down the road, then I will look at replacing the lower intake gaskets. A friend works a Doan Buick. He told me that its real common for the studs to break on the lower intake manifold, which are only 8mm studs. He said on the 95 its not real common to see the lower intake gaskets fail due to the 95 not using dextron coolant.

Jay

the point to do the lowers now is that if you don't you will have to spend more money to re-replace the upper gasket and throttle body gasket.

But if you don't care if you have to spend an extra 50 dollats in gaskets on top of the 60 for lowers, that is up to you.

Well, actually, you can re-use those upper gaskets on re-assembly. It is probably pretty important that the gaskets have never been overheated, that they were not overtorqued, and that it hasn't been many years. These things might cause the gaskets to take a 'set' that will lead to leaks on re-use. I have had my upper and lower intake manifold off twice to replace lifters, (six at a time) and have been able to reuse all the gaskets with no leaks. Saved me $160. To reuse the LIM gasket, you need to be especially carefully to inspect the RTV corner joints. I was lucky - my LIM came undone cleanly leaving undamaged corners. I suppose there was probably a light oil film on the LIM when I originally installed the new lower gasket, preventing a really strong bond on those corners. I did not use new RTV on the LIM re-installations, and it has sealed fine.

All that said, if your lower came off cleanly like mine did, I would take a really close look at those lowers. Look for distortion in the silcone beads and distortion in the plastic frame around the coolant passages. This is a common area for failure. In general, for the $40 cost, I would agree that its a good plan to replace the lowers now too. Then you'll know what you've got.

My lowers looked like junk with only 74k on them. Glad I replaced them while in there.

I made sure I looked at my lower intake gaskets very closely. If my car was a 96 I definately would have replaced the lower intake gaskets, no questions asked on this one. I will keep an eye on the lowers. I just finished up the intake. I go to start the car up, and the thing ran like ****. Check engine light is on. I ask myself whats wrong with this thing now. I noticed the alternator wasn't charging either when I put it back together. I didn't remove the alternator when I replace my upper intake. We'll, I finally I realized I forgot to put the PCV valve back in it. Didn't realize it would run this terrible without it. I notice I accidently busted the coolant temperature switch on the lower intake manifold. So, I replace the coolant temperature switch and now the car runs like a champ again. Put 50 miles on it so far, and the coolant level hasn't changed at all. We're lucky that we have such a fine automobile with the superior 3800 engine. Looks like she'* ready for the long winter ahead of us!