Silly Diff Cover Seal Question

[Bgunner]

I have a 94 Ranger with the 7.5" rear end in it and my question is kind of silly but I just want to be sure of this before I go and do it. My diff cover seal is starting to leak, just a little moisture on the bottom, but whom ever did the seal the last time used RTV sealer instead of the gasket. Can this be done again or is it recommended to use the gasket?

I have run across some rear ends that called for the RTV but none of those I was able to get a gasket for but this truck I can. So what is the recommended way of sealing it? Silly I know but best to be sure. Thanks

 

[adsm08]

I never bother with a gasket.

The stupid things will always leak over time no matter what you do, because the housing and the cover don't expand at the same rate as they heat up.

 

[Bgunner]

I never bother with a gasket.

The stupid things will always leak over time no matter what you do, because the housing and the cover don't expand at the same rate as they heat up.

OK great to know, I have RTV in my box already to no extra expense on me. I always buy high temp RTV so I can use it anywhere. Thanks for the quick response.

 

[85_Ranger4x4]

OK great to know, I have RTV in my box already to no extra expense on me. I always buy high temp RTV so I can use it anywhere. Thanks for the quick response.

It isn't all the same stuff, I like Ultra Black or Gray for things that deal with oil.

 

[adsm08]

It isn't all the same stuff, I like Ultra Black or Gray for things that deal with oil.

Right. The high temp formula doesn't hold oil as well long term. Also there is a gear oil specific formula that I use on diffs.

 

[Bgunner]

Sounds like I should do some searching and reading then. Although I do know for a fact they have high temp in different colors. I have seen it both in black and the funky red-ish orange color.

EDIT: I just checked in the top of my box and I have the Ultra Black and high temp so I'll just use the Ultra Black then.

 

[Bgunner]

Does all gear oil have friction modifiers? I thought is that what the additive for limited slips is for. The reason I'm asking is I looked up the Peratex gear oil RTV and it says that it is formulated to prevent break down due to friction modifiers. I should mention I do not have the LS in this axle.

 

[adsm08]

Friction modifier is for limited slip clutches, but it doesn't hurt anything to put it in an open rear end. Consequently most gear oils you can buy off the shelf have the stuff in it already.

 

[Bgunner]

Friction modifier is for limited slip clutches, but it doesn't hurt anything to put it in an open rear end. Consequently most gear oils you can buy off the shelf have the stuff in it already.

Well in that case I'll try to find the gear oil RTV when I pick up the gear oil. I hate the smell of GL5 (especially when old and burt a bit) so I don't want to do this more often . Then necessary.

 

[Bgunner]

So I just did the diff cover gasket but was curious about one thing. Is it common to have bubbles in the gear oil? What I saw was larger bubbles on the ring gear and carrier barring caps once I popped off the cover.

I know in engine oil bubbles are bad but what about the gear oil?