Will rtv work on this rear diff housing ?

Joined
Jul 24, 2010
Messages
3,541
Location
LONESTAR state
The preview owner must using a screwdriver or something that he put bunch of deep mark into the rear diff housing . I was going to use felpro gasket . But I think right stuff gray properly work better since it fill up those deep mark up
 
Before:
E71CB010-054D-4E84-9664-87677A875F6A.jpeg

After:
8C1335A5-89D2-4B71-8846-775AE825FF26.jpeg

Before/after. I accidentally instilled some gouges on this upper pan while removing the lower pan. A few seconds with a brown 3m roloc disc smoothed the gouges fairly well. You may want to consider doing the same.
 
Before:
View attachment 47646
After:
View attachment 47647
Before/after. I accidentally instilled some gouges on this upper pan while removing the lower pan. A few seconds with a brown 3m roloc disc smoothed the gouges fairly well. You may want to consider doing the same.
Mine look worse then that . The housing suffact is having deep gouges . I change fairly many rear diff and this the worse I seen
 
Before:
View attachment 47646
After:
View attachment 47647
Before/after. I accidentally instilled some gouges on this upper pan while removing the lower pan. A few seconds with a brown 3m roloc disc smoothed the gouges fairly well. You may want to consider doing the same.
I wouldn't take a Roloc to that or any engine or transmission for that matter, the abrasive dust generated by these things can severely damage bearings over time, I wont even use one under the hood for any reason. If the parts are being thoroughly washed and cleaned afterwards like a bare block or housing that's different.
If anything I would just use a very fine file to dress the area to remove anything proud of the surface and use RTV, you could also swipe a bit of JB weld on the mark and a couple of strokes with the file with restore the surface for a gasket.

 
I've used permatex ultra black for my 7.5" diff cover and I haven't had an issue out of it. Permatex Right Stuff Gray is a staple in the drifting community for diff covers, I'm going to pick some up when my ultra black runs out.
 
The preview owner must using a screwdriver or something that he put bunch of deep mark into the rear diff housing . I was going to use felpro gasket . But I think right stuff gray properly work better since it fill up those deep mark up
We need the "this thread is worthless without pics"

how can we really tell if anything will work without a picture?
 
Just draw file off any raised parts of the gouge so the flange is flat, divots won't make it any more prone to leaking but a bump will. Use a thin bead of RTV, hand snug the bolts up and let it sit for an hour or so then torque the bolts to spec. Never had one leak, gasket or no gasket, always used either grey or black RTV occasionally even red and rarely blue. Did a couple with motoseal non-hardening, worked OK, kinda messy but it didn't leak. Only ones I've ever had leak were done with just a dry cork gasket or if I went a fully tightened the bolts without letting the rtv cure for a bit first.
 
I wouldn't take a Roloc to that or any engine or transmission for that matter, the abrasive dust generated by these things can severely damage bearings over time, I wont even use one under the hood for any reason. If the parts are being thoroughly washed and cleaned afterwards like a bare block or housing that's different.
If anything I would just use a very fine file to dress the area to remove anything proud of the surface and use RTV, you could also swipe a bit of JB weld on the mark and a couple of strokes with the file with restore the surface for a gasket.

I contained the dust, if-any. The entire process took under 3 seconds.
 
Gasket makers never recommend the use of RTV in addition to the gasket. If the gouges can be filed/sanded away smooth that would be ideal (covering up the sensitive areas of course). If there's a couple deep gouges I would fill it with JB weld and sand down smooth. The preference would be to get the surface smooth enough to a point where a simple gasket can be used because it makes it so much easier to service for next time. I'd only consider RTV (alone and with NO gasket) if the surface was in absolute terrible shape.
 
There is a ford tech on youtube who does a great job. He took about six or seven shop rags (cotton), and jammed them inside the diff to protect everything, and soak up the old oil.

Then he used a roloc disc to clean up the flange.

If you have one that is not gouged, I would get a set of plastic trim tools from harbor freight (plastic pry tools and scrapers), to make sure you don't gouge up the flange next time.

I would use the sealant approved for oil use, most OEMs do not use a gasket at all, just sealant.
 
I think there is some misinformation in this thread … a well made (modern) factory gasket does not leak … and there are some stellar aftermarket gaskets available … I reuse OEM gaskets and have for years …
not your grandfather’s gaskets … so some leak you can’t forget about from way back is meaningless
Another sealing upgrade is an aftermarket cover … machined/stiff flange + drain/fill/level plugs …
 
Back
Top