Diff leak/cover advice needed (1 Viewer)

[Cruiserhaven]

Large puddle of oil underneath the rear diff, so I wiped it off and was able to observe oil coming from around one of the lower bolts.

Pulled off the cover.

Diff cover on the bottom was a bit mashed, edges seem a bit sharp...

Also found a bit of spongy rubberish debris.

Questions:
What is the debris likely to be?
Should I replace diff cover (I have a cover from boneyard axle) or try to refurbish it by smoothing/grinding rough edges?
For the surface of the diff, what is the best preparation--ex. I have 1200 grit dremel polishing bit I could use?
For gasket, I'm thinking OEM (which I already have) plus some Permatex RTV?


Any advice appreciated, thanks.

 

[CRZR45]

Debris is old gasket sealer. Get a new gasket and reinstall. Get the oil out of the sump so you can clean surface well . You can put gasket sealer on threads of lower bolt as that’s how I drain mine since the bottom drain plug is one with the axle from rock crawling.

 

[Kleatus]

Toyota FIPG or black Right Stuff. No more leaks. You dont need to polish anything, clean with wire brush and brake cleaner is sufficient.

 

[ceylonfj40nut]

Toyota FIPG or black Right Stuff. No more leaks. You dont need to polish anything, clean with wire brush and brake cleaner is sufficient.

I use red stuff on gear oil parts. Black fipg for engine oil areas.

 

[Kleatus]

I use red stuff on gear oil parts. Black fipg for engine oil areas.

Orange Toyota FIPG, black Right Stuff

 

[Cruiserhaven]

Good advice all, thanks! With luck I'll get it all back together next weekend.

 

[Spook50]

Large puddle of oil underneath the rear diff, so I wiped it off and was able to observe oil coming from around one of the lower bolts.
View attachment 3009654

Pulled off the cover.
View attachment 3009675

Diff cover on the bottom was a bit mashed, edges seem a bit sharp...
View attachment 3009661

Also found a bit of spongy rubberish debris.
View attachment 3009667


Questions:
What is the debris likely to be?
Should I replace diff cover (I have a cover from boneyard axle) or try to refurbish it by smoothing/grinding rough edges?
For the surface of the diff, what is the best preparation--ex. I have 1200 grit dremel polishing bit I could use?
For gasket, I'm thinking OEM (which I already have) plus some Permatex RTV?


Any advice appreciated, thanks.

From when I rebuilt my rear diff a little over a year ago:

FIRST AND FOREMOST: get a new OEM cork gasket. If OEM calls for a gasket, use a gasket and not FIPG or RTV. I have never once used RTV on my rig and only ever use FIPG where the FSM calls for it.

COMPLETELY remove all remaining gasket material until you have a clean surface. With cork gaskets, Brakleen or carb cleaner work (electrical contact cleaner works great with paper gaskets as it quickly breaks down the adhesives in them), and absolutely use a wire brush! Get all the remaining material off so you have a clean surface.

Use a thread chaser (if you don't have a set, GET ONE! They are invaluable on these old rigs) to clean and reform the threads on the studs. Taps and dies are not good for cleaning threads as they will cut material away, whereas thread chasers clean and actually straighten threads without removing material. If any studs come out of the housing in the process, no worries. Simply reinstall just until snug with some blue Loctite.

Reinstall the cover, torquing the nuts to what it calls for in the FSM, tightening in a star pattern like you would with lug nuts. Don't exceed the specified torque or you crush the gasket too much and it'll almost immediately start leaking.

After driving it for a month or two, retorque the nuts

Been a year since I did my rebuild and not a single drop yet.

 

[Cruiserhaven]

Thanks!