Best Gasket Sealer

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custodian

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I getting ready to replace the gasket on the rear end on the 85 C10. Which would be the best gasket sealer, Permatex High Tack or Permatex Gear Oil RTV?
 

scrap--metal

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In my experience, rear end covers are pretty easy to seal. Just about any RTV/gasket sealer should work as long as the diff isn't filled to soon after assembly. No gasket necessary.

If you're eager to dump fluid in it immediately after sticking the cover on, use whatever sets up the quickest.
 

custodian

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In my experience, rear end covers are pretty easy to seal. Just about any RTV/gasket sealer should work as long as the diff isn't filled to soon after assembly. No gasket necessary.

If you're eager to dump fluid in it immediately after sticking the cover on, use whatever sets up the quickest.
Will not be refilling immediately. I have both sealers.
 

squaredeal91

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Always been a big fan of the gray. Never heard of this right stuff till now, I'll be trying it for sure. Thanks!!
 

custodian

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I ended up using the Geare Oil RTV.
 

PrairieDrifter

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I use right stuff. Be prepared for a slight fight to get whatever it's sealing off. But id take that trade off any day of the week.
 

Doppleganger

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Anything diff, trans or transfer case that leaked.....the Permatex Gear Oil RTV always stopped it for good. Anything else leaked.....eventually.
 

Octane

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I use gear oil resistant rtv. I used to just use a gasket only. But it was just such an ordeal to make the local partscounter jockey get a 12 bolt gasket, instead of the 10.
 

Daron58

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High tack all the way use it for all my stuff rear diff cover,side lifter covers,valve covers, oil pan etc. one time and done when re-sealing anything
 

CalSgt

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Ive been using Permatex “Gasket Maker” and it’s done well. That’s what came with the Spicer differential bearing kits I bought for my Jeep.

Ultra grey is my go to. It's good stuff.
This too

ETA: I also like the “Lubelocker” reusable gaskets that don’t need goo to seal.
 

metal tech

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I read recently about an idea of helping an RTV sealed area not leak. Don't fully torque the bolts, but allow the RTV to "firm up" then torque to spec. I do have to second the Lube Locker gaskets, I have not had one leak yet, and they are reuseable if taken apart carefully.
 

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