I have some pictures of my 1994 Bonneville'* lower intake manifold gaskets. It was once forced thought that Series 1 engines did just fine with regular coolant and didn't eat gaskets. Well, not so! I mean, you'd probably need to think for a second about nylon gaskets between aluminum and iron so as to realize that they'd change shape, but sometimes that just doesn't feel like common knowledge.

My 94 Bonneville had recently had its third or fourth engine rebuild when I bought it and put about 12K miles on it. Then the oil pressure started dropping, there were weird noises, and I decided to go for an engine swap with a turbo. So, I took out these gaskets.

Let'* observe.

Nothing wrong with those gaskets. Dexcool killed them. Can you see me rolling my eyes?

I posted a thread a while back, stickied I believe. The plastic LIM gaskets need to be avoided at all costs. Aluminum gaskets only. If they don't have them, then wait. Do not use the OEM plastic gaskets.

Yes, I remember your thread and I really like it! I'm absolutely for the evidence you presented. The nylon/plastic/other gaskets for the Series 1 LIM show the same cracking as you had when you pointed out points on the Series 2 gaskets.

That'* the thing I never understood about it. S1 or S2, Dex or no Dex... still failing gaskets. How could someone blame one coolant, even if it wasn't present.

Because some people refuse to accept the evidence laid out in front of them because they so desperately want to be right.

I talked to a few dex cool hatred converts, and it seems they say that Series 2 gaskets fail and also the dex gums up. I say often to these remarks that yes, dex gums up, and yes, gaskets fail, but they can happen independently so they aren't related. Besides, on a dexcool engine with failed gaskets but good looking coolant, you could just chemically analyze what'* up with the coolant and see that it has neither turned acidic nor has chemically bonded and created new molecules out of nylon leftovers.

Dex will sludge up if it gets air worked in to it, or if the system is topped off with something other then Dex. When a LIM gasket fails it can allow air in to the cooling system. And that causes sludge. When you step back and look at the whole picture, you can see the plastic LIM gaskets are the cause of the problem. Or, you can view it with tunnel vision and blame the DEX.

Well, tunnel vision is beneficial in that saves you the hassles of considering multiple possibilities and thinking a lot.