Drive shaft stuck in AMC 20

[Hairball29]

Hi, all

I've got a 79 CJ5 with, I think, a 78 rear end (because it has 11" drums which as far as i can tell weren't on 79s)

Anyway, I'm restoring the thing so I wanted to get the hubs apart so I can inspect, clean it up, change the oil seals, etc. I was able to get the passenger side apart with a hub puller, then i removed the drive shaft very easily. No problems so far

The other side, however, is a lot less willing. I've broken one puller already, and have upgraded to the much stronger version that holds the wheel studs.

I've applied as much torque as I can with my breaker bar, and impact gun hoping the shock would help. I've tried heat, been soaking it with penetrating oil for a week but it will not budge, so i gave up and decided just to pull the drive shaft from the diff instead and take out the whole unit. But now that ALSO won't come out. I've only tried a slide hammer so far because that's all i can think to do

I think the seals failed and water got in. I'm guessing it made it as far as the diff and so rusted the splines where the diff and drive shaft meet so now I, and it are stuck

I can't find any advice online for when they get this stuck other than what I've tried already.

Can anyone point me in the right direction when things get this bad?

Thanks in advance

 

[jp360cj]

1st, welcome to the forum!

2nd, just to clear up some possible confusion, what you are calling the driveshaft is axle shaft. Drive shaft usually refers to the shaft between the Transfer Case and axle pinion.

As you have found out, removing the hubs can be a real chore. The last time I did it, one side came off easily, but for the other side, we left the puller under tension for almost 24 Hrs, sprayed penetrating oil on it (was probably either Kroil or PB Blaster) and then hit it with a hammer and it popped off. But DO NOT stand in front of it.

For removing the shaft, is it moving at all, or completely stuck? are all the mounting bolts removed from the backing plate? Maybe a bigger slide hammer?

 

[Hairball29]

Hi, thanks! glad to be here

Yes, sorry for the cross terminology. I do mean the axle shaft, the one that connects the hub/wheel to the diff.

I've tried leaving it under tension overnight, but perhaps not as much tension as I could have. I'll try again tonight and see if i can persuade it with force and more oil.

The other was easy. It came off with just a few turns of the puller.

I'll have another go at the whole shaft. One thing that's slowing me down is i don't have the best grip with the slide hammer. I'm using one of those internal spreaders you might use for an internal race, and i'm trapping it inside the half-installed nut on the end of the shaft. It holds for a bit the lets go after a few blows. That was enough for the other side, but I think I need a more solid connection. I haven't been able to come up with one using my tools yet.

 

[mriplaybass]

I assume you have unbolted the brake backing plate, and pulled it away from the axle tube. Spraying penetrating oil into the bearing and letting it work is always a good idea.

A couple years ago, several of us were installing 1 piece axles on a CJ7 prior to the Colorado trail ride. The drivers side axle came out easily, but when it came to the right side, the project came to a screeching halt, and we didn't know if we would get it done in time for the ride. Even the biggest puller available from the local parts house wouldn't budge it. This may seem odd, but what ended up working was one of us wedged 2 large screwdrivers between the axle flange and the brake backing plate (which was tight up against the axle shaft flange) then the other guy worked his way around the axle shaft flange (the outer part with the wheel studs) with a big hammer while screwdriver guy pulled alternately on each screwdriver. Eventually the bearing began to wiggle, and out came the axle shaft. This process took about 20 minutes of banging vs several hours of everything else.
There was not really a lot of pressure necessary. We didn't want to bend the brake backing plate, so the pry force wasn't excessive. If you try this, make sure that you don't put the screwdriver blade directly against the axle tube flange. Use a piece of wood or something to protect the flange face.

 

[Hairball29]

I managed to get the shaft out. I think the backing plate was a bit stuck, so some persuasion there and a bit more slide-hammering set it all free.

The Shaft and hub are still very stuck. They've been left under tension over night to think about what they've done. I'll have another go at it tomorrow.

Thanks, everyone.

 

[mtnwhlr]

You may need a press to get them apart.

 

[JeeperChris]

"...to think about what they've done..." LOL

 

[Hairball29]

Friends, I gave up!

Reluctantly, mind you. I Dremel'd the bearing and its race off so I could get the brake backing plate off and cleaned up, then I put the shaft into my 12 ton press and gave it all 12 tons to the point that I could no longer move the jack/pump handle, and the bottom support was starting to bow.

I figured if it did let go it'd spear someone or something I value, so I've decided cut my losses and get a new shaft, hub, bearing kit instead. I've killed one puller (this one appears to have bent the hub flange slightly, too), damaged another and my press was under threat so this seems like a cheaper option!

I'd swear it was welded together. Water definitely got in there as I can see rust on the back side of the splines, so I guess that seized it. At some point I might cut it open with a grinder to see what defeated me

thanks again

 

[jp360cj]

How much did the 1 shaft and hub/bearing kit cost? Unless you just want to keep the original style, you are at a good point for a 1 piece shaft upgrade. You can get cheap ones for ~$200 and top of the line (Moser) for a little over $300 last I checked.

On the last 1 piece upgrade I did, I had an extra set of backing plates (well, the guy I was installing them for did), so I didn't even bother with removing the hubs.

 

[Hairball29]

I went with the original style, Omix brand. i think it was 116 including shipping for the shaft, hub, bearing and seals.

 

[Hairball29]

So I finally got it separated! sawzall'd through and got to about 1/16 of the shaft lest i go too far and damage it. Then i put it back in the press and finally the thing let go.

It seemed that the penetrating oil got all the way into the taper and the splines, but it wouldn't release without the above treatment.