Wedge Diff Cover Gasket Adhesive

[JFS]

After having my rear differential rebuilt a couple years ago, the rear cover now leaks. The sealant used by the shop appears to be a red RTV. What sealant should I use with my new rear cover gasket? Any suggestions?

 

[Darrell_Walker]

In theory it shouldn't need anything. What often happens is the bolts are torqued too much and distort the cover, make sure the flange is flat.

That said, I like to glue gaskets to the removable part (cover) with RTV, and use a non-setting sealer (hylomar or the like) on the other surface.

 

[TR3driver]

What he said, except I use Hylomar on both sides. The important bit is getting the sealing surfaces perfectly flat.

 

[JFS]

Thanks Darrell and Randall. I'll work the cover flat and look for some Hylomar.

 

[TR4nut]

I tried to use hylomar but apparently I had some distortion on the cover - couldn't get a seal. I went with a permatex gasket sealant (non-rtv type) and it's been leak free. I wasn't worried about destroying the gasket as I rarely open up the case and it's easy to clean up the surfaces.

 

[justin_mercier]

I just picked up some RTV in a black tube made specifically for diff covers. Supposedly it holds up better with gear oil than the red RTV

 

[DNK]

Justin- What's the company name

 

[tr8todd]

There is a trick to installing diff gaskets and oil pan gaskets on the wedges. Coat both sides of the gasket lightly with your choice of sealant, and let it sit for a few minutes so that it starts to dry. I like black RTV because it doesn't look stupid when it squeezes out like the red stuff does. Install the gasket, cover and bolts, but only tighten them a little bit. Go back the next day after the sealant has had a chance to set and torque the bolts down. If you try to torque it down with the sealant wet, the gasket will stretch and squeeze out the sides.

 

[JFS]

Thanks tr8todd!

 

[DNK]

Did that with my oil pan when I installed it with the "Right Stuff"
Well see how it comes off when the garage climate is a little more reasonable

 

[justin_mercier]

Permatex Gear Oil RTV Gasket Maker

"Specially formulated for differentials and transfer cases to resist modern gear oil friction modifiers that can break down normal RTV and cause leaks.

Justin- What's the company name