I never use a paper gasket for any year. As long a the rubber 0-ring in in good shape, and surfaces are clean/smooth you won't have issues. The rubber o-ring actually creates the seal.

Let me clarify

I used only the rubber o ring that surrounds the thermostat. It does protrude above the surface of the lower intake manifold and seals to the water outlet very well. The paper gasket that is expected was not used.

There is no need to use RTV unless it is recommended or your surface area being sealed is not a good flat surface. RTV would make changing the thermostat more difficult than the paper in most cases.

From this point on..(being that I would change a T stat on a wimp) I'll be running w/o the paper on my Series 2. All Series 1 owners should still continue to use the paper.

I had mine on without the gasket for about a week, but then I kept getting a faint coolant smell. Upon close inspection, I then noticed an orange like of gel (Dex-cool) around the T-stat housing-to-block mating surface. The coolant had ever so slightly seeped out, but it would dry to a gel before it formed a drip.

I installed a housing-to-block gasket from NAPA and had no more seep since then.

It should be noted that if you have ANY pitting or corrosion due to age, you should continue to use the gasket.

I have no issues with the paper gasket personally. I use a very thin skim coat of blue RTV on each side of the paper. It pulls right off cleanly when I need to change it. Then a small wire toothbrush cleans of the RTV remaining.

I was gonna say that the purpose of the gasket and/or sealant is to prevent the metal on metal contact which would promote corrosion, wear, etc. increasing the chances of leaking. If you don't like the idea of the paper, a good high-temp sealer, applied thinly would be better than nothing. I generally apply a thin bead, schmear it a bit, let it dry a bit, then another thin bead and put it together.

Again, I have not yet done this with the Bonne. Until I get one apart myself, I'm just speaking from experiences with other engines.

Metal on metal does not promote corrosion, rust or any other items. A thin layer of RTV should not be needed. If you need RTV, then the pitting and issues are at an advanced stage.. 10 years old with 8.5 being fillted with DEX.. the manifold and outlet on my car were not pitted or corroded. Leaks will promote corrosion and goop.

The FSM directs us not to use any extra adhesives or sealants for a reason.

Sorry, I don't agree with you Bill.

My surfaces are perfect and just as MacDrive indicated they will weep ever so slightly. Just enough to create a stain and look like crap after a few months.

The RTV smear is so thin, it is non existent when you remove to change a stat and believe me I've done it a lot on this car in the last 7 years.

Ok..well.. GM swapped over and we know they didn't make every decision intellegently. Guess I'm running a test to see if I get any seepage.

I HATE when I get seepage.....oh.... ...I guess you are talking about the thermostat...

RTV will fix that too. Might get a bit uncomfortable, though.

And, I just personally don't like the idea of no gasket at all. A thin coat of goo gives it a bit of cushion if nothing else. And yes, I mean the thermosts housing this time...