Gasket, yes or no?

[fng]

I have both the front and rear diff's open right now and plan to seal them up tomorrow. I found in a previous stash of parts a pair of original, NOS fibre-like gaskets for each. My question is should I use them or just dope it real good with Mega-Black and cinch it down?
I ask because I read somewhere that a guy never could get a diff to quit leaking using the gaskets?!? Truth or fiction?

[Chumley]

I've done it both ways and have had no real issues with either. I do prefer using a gasket though.

[randyscycle]

I'm with Chumley on that. I've used both as well with no real problems but if a gasket is available I will use it first.

Just be sure that you get the cover good and flat on its gasket flange and everything is clean and dry. That is the biggest problem with not being able to seal anything really, is cleanliness. Also be sure to use the correct original flange type bolts to spread the load evenly on the cover when its tightened.

[fng]

Cool, two votes for the gasket. I was leaning that way too. Thanks.

[Kaiserjeeps]

I like to use gaskets if I have em. I really like a gasket with the smallest pencil lead bead of RTV on both sides because it seems to assist with long term sealing. It seems to me that a gasket alone can sometimes loose it's sealing integrity over time and a rock or two.

[cherylsm515]

i,ve put well over 100 diff's in semi trucks and never used anything but permatex ultra black silicone. not 1 leak and some have gone over a million miles. those gaskets are old school thinkin before the good silicone was around.JMO
RON

[fng]

I used both yesterday, I actually doped it on the metal parts and sandwiched the gasket in the middle. I hope it doesn't leak, nothing more pesky than a dripping truck.

[randyscycle]

those gaskets are old school thinkin before the good silicone was around.JMO
RON

I really don't have much problem with gaskets. Again, get the flange flat and clean. Many of the older differential covers weren't completely flat anyway. They had a bead in the sealing surface, so if you use just RTV, you need a lot of it to fill the gap. Too much in my opinion. Remember, what you see squeeze out is also squeezing to the inside as well.