8 3/4 pumpkin gasket/sealer?

All,
Putting the rear end together for my Demon.
Trying to do everything the best that I can, and want to make sure from all of the professionals - since I haven’t done all of this since about 1989!?!
When putting the pumpkin in, what is the best gasket to use?
Is any sealer needed? If so, which one? (Blue/Black/cooper?)
Thanks in advance everyone!!

Wally

If you're parts are clean and in good condition - no sealer is needed. The factory didn't use it.
Fel-Pro makes a good gasket - just got mine from Dr. Diff. Most auto supplies offer them too. If you plan on remiving the pumpkin you may want to put a very light coat of Lubriplate on the gasket so it doesn't stick.

Done that on my race cars for years - saves the gasket and clean up time.

"the right stuff" rtv in a cheese can. It's not cheap, but I haven't found anything better, no gasket needed.

IMO, either would work fine. I've had good luck with just the part-store gaskets, but I've only changed my pumpkin once. If it looks pitted on the surfaces at all you might want a bead of RTV. You don't really need any gasket tack because the gasket will stay in place on the housing studs.

And don't forget those pumpkins are heavy when you're trying to lift it up into place & start some nuts! Now would be the time to put a rear end gear ratio tag on there too.

fyi- I have a 71 Mr Norm Dodge Demon 340 six pack air cleaner. PM me if interested

Gasket dry has worked for me if mating surfaces are smooth. Or a little black RTV on the gasket if surfaces are rough works fine. RTV only can work but not really recommended.

With RTV it is best to install the gasket and torque lightly. Let the RTV set up for an hour or so then full torque.

If you do use RTV it is important that surfaces are oil free. No seeping lube anywhere and clean with lacquer thinner first... preferably several times.

Permatex makes a gear oil specific sealer. Want to say the tube is grey with white lettering? It does work good and you can get it apart without using a hand grenade.

I stopped buying the generic blue and black RTV and have been seeking out products that are more tailored to whatever fluid it's making contact with.

I once put a Ford 8" rear together without a differential gasket and it didn't leak. If the two mating surfaces are flat it's totally possible.

Good info posted. I'm assuming it ain't gonna be coming out again soon. I would clean the surfaces well/get a parts house gasket/some Indian head brush on sealer. quick easy cheap. On a toughie (stat housings) yes "the right stuff" seals em when sometimes nothing else will (thermostat housing mating surfaces are too narrow).

Robert, just did a swap in mine and that's what I used, cleaned both surfaces hospital clean (acetone and a dry rag until it all passed the white glove test) then a thin layer of Indian Head sealant on both surfaces. Worked like a charm, no leaks, and its easy to remove down the road.

IMHO.. I would use one of the superformance non stick gasket or get a seal kit from Dr Diff with non stick gasket.

you can get the axles seals and the foam/bead end gaskets for the backing plates from Dr Diff as well.

thick non stick and reusable.

both good sponsors here on moparts!

Ultra Grey silicone here, no gasket. Nothing wrong w/ using a gasket, but I always have silicone on the shelf.

To the silicone/sealer users: how much time do you spend scraping that off both surfaces?

Thank-You...

I have pulled rear centers dozen times I use silicone but have found it will leak The Indian head stuff wiil not leak So gasket and that you should be good to go

A thin smear of wheel-bearing grease on both sides of a good paper gasket has always worked for me. I really really hate leaks, but I also hate it when parts are glued together or you have to scrape gaskets off.

Superformance gasket with a smear of brake grease to keep it from sticking and makes removal easier

Gus

I also use the Permatex Gear Oil specific RTV. I also use the gasket from any of the parts stores and use this sealant on both sides. I have used it the last two times I pulled mine and it has not leaked. It's a good product 👍

Got it put together boys!
Used the right stuff, and a paper gasket.
I want it to stay together and be leak free for a long time.
The right stuff really seems like good stuff.
Thank you all for the advice!!

The "Right Stuff" is a very good product and will likely not leak.....Just pray that you never have to remove it because that stuff is the "Super Glue" of sealants, it can be a grisly task to remove it!

This is what I do as well; only used RTV once and hated the clean-up when removing and reinstalling the unit. Grease and a Felpro gasket is cheap and easy.

As said (by some) just me I would not use RTV or TRS in that app, too much scraping to get the RTV off if you think you might be swapping pigs soon (most wouldn't be tho) & with TRS I'd about wanna put a nut on em & drive out the studs before attempting to scrape that stuff off. with cleaned surfaces expecially at the base of the studs, that a dry gasket would suffice, maybe a premium superformance one & even lubeing the gasket if frequent changes are anticipated. You do have a fairly wide contact area there. #1 check for debris.

Thanks Robert!!
I don't plan on swapping it out anytime soon - but, you know how the best laid plans go....
If I ever go to experimenting with gear ratios, I will definitely try a good gasket and grease.
I made sure both surfaces were hermetically clean before the thin bead of TRS.
My memory reminded me to torque the nuts to 45 ft. pds---sound right?

iirc 45 yes. & hermetically clean is even more cleaner than surgically clean right! (no oxygen present?).

If you are going to the drags 70/30 with an 8.75 then it will be apart again.

This is true. I had to go back in and remove the whatever pin within the suregrip to use green bearings. I believe breaking the seal on the 3rd involved hydraulics.

That being said, I don't really need to get into the 3rd member on a remotely regular basis.

Should have just removed the green bearings and left the 3rd member in there.

If you need to keep removing the pumpkin, you have more troubles than trying to get silicone off the housing.

Anybody could have problems, but somebody else may want to change gear ratios.

http://www.loctite.com.au/3320_AUE_HTML.htm?nodeid=8802626633729

Wilwood brakes require them.