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8 1/4 clean up, possible rebuild

JR_Charger

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When I got my Charger, somebody had replaced the vent bolt with a regular bolt, resulting in this big gooey mess -

differential-leak.jpg


I've spent days cleaning the diff up (replaced the regular bolt with a vent bolt, changed the oil and replaced the diff cover gasket), only to find oil seeping out around the axle and these plugs -

01-differential-plug-leaking.jpg


02-differential-plug-leaking.jpg


(the non-venting bolt is temporarily back in while I clean and paint, will be replaced with the vent bolt when I'm done)

I was planning to use this rear end for a while, and I suppose I still can. The seepage is slow enough that I believe I can clean it and get the finish on. Then maybe it will seep over the finish, or some of the finish will fall off but overall it will still look better than a completely rust colored rear end. It's going to be temporary. I'll put in an 8 3/4 later and then this 8 1/4 can be rebuilt. AFAIK it takes specialist knowledge and tools to pull the axles and put them back together again right, so I'm dubious about trying that, even though the rear end is out. I might be able to replace those plugs though. Don't know, how hard is it?
 
It could be possible that with the proper vent back in place, it won't build up any tiny amount of pressure and those weep points will stay dry.
 
I agree with Photon440. Keep shooting a little brake clean on those spots and they should dry up enough to paint.
 
If you want, di-grind.Clean very well with brake cleaner. Then mix up some JB Weld to seal the plug welds.
 
Let me clarify a little - this rear end has just been sitting here, not in any kind of use at all. I clean it up, the weeping is back the next day. Is the air pressure change of the weather enough to cause the weeping? Maybe it is. I was thinking it would need to be in use to push oil out, but perhaps the day/night cycle alone is enough.

I was going to go clean it some more in a few minutes. I'll stick the vent bolt back in and we'll see what happens tomorrow. It would be great if I could get on with painting the rear.

What color are these supposed to be anyway?
 
The vent bolt made no difference. Just as much seepage as before.
 
Found an article about rebuilding the Ford 9" - link

I didn't realize there's a rubber seal at the end of each axle, and the differential pinion seal is also rubber. The Mustang builder says any rubber over 30 years old should be replaced. 50 is more than 30 . . .
 
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