8.8 differential cover- paper gasket or RTV or BOTH? please input

[1990 HOSS]

I was just wondering how most people seal up the differential. I bought a Felpro paper gasket at autozone. Then, I happened to think that I may need some silicone gasket maker, so I asked the guy at autozone and he recommmended the heat resistant RTV silicone (red). But I have little faith in what he told me due to the dumbfounded look on his face. So, now I'm asking the real Pro's. Please help me out. I'm planning on installing cover this evening. If you reply with what method you used please also add if your satisfied or not. Thanks everyone.

 

[capriman86]

Mine is resealed back up with silicone gasket only, crap I can't remember what color now.
But no leaks

 

[1990 HOSS]

thanks for the reply capriman. I've read alot of people use the grey and black RTV, but few people say anything about the red.

 

[Mustang5L5]

I've only used RTV....black from what i recall.

 

[85_SS_302_Coupe]

I didn't even know they made an actual gasket for it...lol.

Black RTV here.

 

[faststang90]

its not a 8.8 but i just stuck a 3rd member in the car and they had a clear rtv for rear ends. got it at hi/lo

 

[NIKwoaC]

I took the paper gasket and lined both sides with a thin bead of black RTV. Overkill? Maybe, but gear lube stinks and I don't want it on my garage floor!

 

[LiquidGT]

The T/A girdle I have came with a paper gasket, I plan on using the gasket and black or grey RTV.

 

[RYC CUKR]

I always have used black RTV alone. I know that when I pulled the diff cover on my 03 Mach 1 there was no gasket just black RTV and I bought it new so that is the way it came from Ford.

 

[Maryland Stang]

Mine came with sealer only but it now has sealer and a gasket.

 

[93 LX]

RTV everything! LOL gaskets suck!

 

[Hawkeye_306]

Don`t worry about the color as long as it is rated for enough heat. I used red, because that is all that is needed for the heat in the rear end. But black is fine, or anything else with adequate heat resistance.

Scrape off all the old gasket, and use some brake cleaner to prep the surface (brake cleaner evaporates leaving no residue).

I put on a ¼ bead, put in the bolts at a turn or two past finger tight. Then let the silicon set up for around ½ hour. Then torque the bolts to speck. Remember, there is not much pressure in the rear end compared to the typical engine application. You mainly want a good “lubricant-tight” seal. You don’t want to squeeze out all of your sealing silicone.

I would never use a solid gasket.

 

[1990 HOSS]

Thanks everyone for your input. I took the red RTV and gasket back to autozone and got the black RTV. Absolutely no leaks so far so I'm very pleased with the black RTV. Thanks again.

 

[57fairlane]

I think the factory service calls for just RTV . . .

I just used grey on my t/a girdle

 

[snakebite01]

well i used red only because the rear diff gets hot and the red rtv is meant for heat, but any rtv will work.