8 3/4 teardown-HELP!*Update*

[72bluNblu]

Ok, so I finally came upon a b-body rear for my Challenger, hello spring relocation kit  . I picked it up, guy says its been sitting for awhile and doesn't turn. I figure no big deal, rusty, blown whatever. I just want the housing really, so no problem. Its definitely rusty, the backing plates and out are really rough. But the housing and 489 (score!  ) center section look fine. But nothing turns, not the axles, not the pinion, nada. So I figure I'll tear it down and check out the damage, but again, I really just want the housing, the rest was gravy. So I pull the bearing retainer nuts on both sides and loosened up the nuts on the 3rd member.

Now comes the problem- I can't free the axles. Not prying, not a really big slide hammer, nothing budges these things. Not even a little.

Did I miss something? I should only have to pull the 5 nuts on each axle bearing retainer right? The bearing retainer plates are free, but nothing else moves. Would taking the pinion apart buy me anything? Also, this thing is dry near as I can tell, no oil inside leaking out even though I broke the seal on the 3rd member (which moves a little, but obviously won't lift out because of the axles). Should I tighten the 3rd member nuts back up and fill it with gear oil and let it sit and hope for the best? Or Marvel mystery oil or ...anything up to and including something that will dissolve the axles so I can get them out and keep the housing 

Just for info, its got 2.94 gears with a 489 case, and its not marked otherwise so I would assume its an open diff. I doubt anyone would get their '69 charger with a 2.94 sure grip!

Thoughts?

[72bluNblu]

Small update-

The case isn't totally dry, there is actually a little seepage of oil out of it. Not full by any means though.

Also, the pinion turns a little. It feels pretty "notchy", and only goes a few degrees in either direction. The axles don't move with it though...

[Chryco Psycho]

this sounds like fun ... the axles generally will slide out of the housing once the 5 nuts on the retainer plates are removed , sounds like the brgs are rusted into the housing ends , Penetrating oil / heat is where I would start & a good slide hammer

[72bluNblu]

That's what I thought CP, the axles should slide out pretty easily. Based on the pinion turning a little and the axles not moving I'd have to say that I agree, the bearings must be frozen into the housing. But after hitting it with WD40 and a BIG slide hammer the only thing getting loose is my elbow!

Maybe if I get a rust remover type product I could pour it in there...Or figure out a way to soak the ends of the housing. Its a little difficult to deal with because of the weight though.

[70burntorangeT/A]

72blunblu i tried to pm you but your inbox is full

[72bluNblu]

72blunblu i tried to pm you but your inbox is full

Oops! Thanks for the heads up. Should work now!

t sounds like the brgs are rusted into the housing ends

Hey CP- I'm not to this level yet, but I know they make replacement housing ends for the 8 3/4. How hard are these to install, and do you think if I grind the weld at the housing ends that I might be able to slide the whole housing end off the housing tube with the axle? I've got a few things to try still, but I'm just looking at options...

[Chryco Psycho]

yes they sell housing ends but not for the tapered brgs so I would do whatever I could to preserve the housing ends & retainer plates , you can beat on the backing plates if that helps , it is easier to get new backing plates later if nessisary although this could damage the retainer plates , I would troch out the brgs inside the housing before I cut the housing ends off

[72bluNblu]

Oh! Didn't know the new housing ends were just for the non-tapered bearings. Ok. Well, I still have a bunch of stuff to try. The backing plates are pretty rough anyway, and I have an entire 11" brake set up so I really don't need them. I had thought about cutting one of them off (the one that's really rough) to get better access to the bearings and so it would be easier to soak that end of the housing. If I can get one of them out I think I'll be in better shape, I might be able to use a length of pipe as a drift to pound out the other side then.

This is turning out to be a lot of work! 

[Chryco Psycho]

use a real penetrant not WD 40 & heat
 don`t damage the axles they are shroter than the E body ones

[72bluNblu]

Good grief! This is turning out to be a real problem! So I hadn't been making any headway with the slide hammer. I decided since the left backing plate was pretty gnarly looking that I was going to cut it, I figured I didn't need another set of 10" backing plates since I A. already have a set and B. also have an 11" set ready for the Challenger anyway. So I cut a section out and was able to use a 3/4" steel rod for a drift to pound on the back of the axle studs. Seemed like a good idea...

But NOTHING MOVED. Not even a little.  The solid steel bar mushroomed, but thats about it. Although by removing part of the backing plate I can probably get more penetrating oil into the bearings for the big soak.

As icing on the cake, I somehow had a bad feeling about cutting up the backing plate. I hate ruining parts, even if they are rough. So I figured I'd measure it and put my mind at ease...

It measures 12".  Its an 11" drum backing plate. I measure the really nasty looking leftovers of the brake shoes. 2.5". Perfect.    So now I've probably totaled a 11"x2.5" backing plate. And made no headway as a result. 

I'm beginning to wonder if I'll be able to salvage the axles. If I have to take heat to get 'em out I probably shouldn't use them. Especially with all the beating. They still look fine, but they definitely weren't designed with this in mind. I'd thought about buying new ones anyway, looks like it might become a necessity. So now I guess I'll soak them in more penetrating oil and wait a few more days...

[shadango]

Been watching your situation, as I am considering pulling the axles/rear chunk on mine to check things out since the car sat for a very long time supposedly....but wasfearing getting into exactly where you are....LOL

What penetrant are you using?

PB Blaster seems to have saved my butt a few times....Spray it down, let it sit a day, try.....if no luck, repeat.

There are probably otehr great ones out there...or maybe they are all the same...but PB works great for me...

good luck! I have my fingers crossed for you!   

[dougs bs23]

perhaps a mixture of 25 psi oxygen and 3-1/2 psi acetelyne applied to the housing over the bearings, then the slide hammer will break it loose for you

[72bluNblu]

Well, first  tried WD-40 but it doesn't work very well as a penetrating oil for this stuff. I've poured some Marvel Mystery oil on there and let it sit the last couple days, but I haven't tried it again yet. I think I'm just going to keep applying more and wait a bit. I also ordered some Kroil, I've heard its great stuff, maybe even better than PB blaster. You pretty much have to order it though, which is why PB blaster gets used more often since its carried more places.

The only thing I'm concerned about with heat is the axles, heating them basically undoes the hardening on them. Obviously temperature plays a big role in that, if you can keep the temperature low it shouldn't be a problem. I'm just going to take it slow and see what I can do. I will get this thing apart, hopefully I can use the axles afterward. If not, then I guess I'll have to buy new ones...

[Chryco Psycho]

you might be able to tap the brgings into the housing witha punch & big hammer to loosen the grip

[72bluNblu]

you might be able to tap the brgings into the housing witha punch & big hammer to loosen the grip

 

Interesting. I've tried pounding the axle "in" a few times to try to break it loose, but it the whole axle might not move in because of the block in the middle right?

Only other question is, can I get any of these retainer parts to keep the stock type bearings if I damage them?