12 bolt differential pinion shaft removal

[dmjlambert]

I want to remove the c-clips and pull out the axle shaft. This 12 bolt differential is giving me a hard time or I don't know what I'm doing. On my 1969 differential I removed the differential pinion shaft lock bolt and the pinion shaft fell out. On this 1963 one I was able to remove the lock bolt intact. But I can't get the pinion shaft to come out. I tried pushing it from both sides, and I tried using a socket and tapping on it with a hammer (lightly). It moves about 1/8 inch. It can rotate with the gears. What to do?

[dmjlambert]

http://www.youtube.com/watch?v=WfPleGYBbZY

Here I show what I'm trying. I removed the lock bolt, and tap on the shaft until it stops, then turn the gear 180 degrees and tap it back the other way. I think it is getting to have slightly more movement, but only barely detectable amount.

I have been thinking about putting the cover back on, and filling the case with vinegar and rolling with it for a dozen miles, to dissolve rust. But the truck is not yet running so I'd have to hook up a tow bar and disconnect the drive shaft and pull it, which sounds like a lot of trouble. Another thing I've been thinking about is putting the lock bolt back in, turning it to the side that doesn't have the lock pin, and drilling and tapping a hole and perhaps use a slide hammer to get it out.

[bigmoe]

It's been a while since I did mine but I don't remember having any difficulty removing the pinion pin once the pin bolt was removed. Maybe a little more persuasion? Don't let those pinion gears fall out. To clean it I'd just hand remove as much sludge as possible and then hit it with some solvent.

[Mike C]

Extremely worn differentials often have the shaft cut into by the spider gears. These require pretty significant hit to move. I use a drive and try and drive it as far as I can out the other side of the case and have the differential where it will still rotate. Then when it’s facing you grab it with a big pair of vise grips and wiggle if it doesn’t come out.

[rbruno68]

I may be doing the same thing this evening. Look for a new video on my youtube soon. I hope mine comes apart a little easier.
OLDMD 63C10

Rob

[dmjlambert]

Thanks for everybody's input. I finally got that shaft out by using a bigger hammer as suggested (significant hit). If the first thing you discover doing yours is a broken differential pinion shaft lock bolt, there's another post of mine about how I dealt with that.
To remove this one I used heat when breaking the lock bolt loose.

[54blackhornet]

You must have the patience of job !

[Rust_never_sleeps]

Was there just an accumulation of crap on the shaft preventing it from going willingly through the gears?

[dmjlambert]

I have not figured out what was blocking the pin from coming out. Member RustyPile PM'd me and has given me some homework and procedures to evaluate the condition of stuff in there.

[rbruno68]

Mine was filled with about an inch or two off gooey sludge. Not rusted like yours, just black sludge and smelled terrible. Mine did come apart pretty easy though.

[dmjlambert]

In the daylight I can see there appears to be some scoring of lines on the shaft where the gears go through it, and the surface inside the gears is mostly smooth but my finger can feel some irregularities. The shaft absolutely will not go into those gears by more than the first 1/2 inch. The shaft will easily go into the carrier and pin in place. I left these 2 gears out and put the pin and lock bolt back in the differential to hold the assembly together so I could put the truck back on the wheels, and move the truck around the garage on its roller skates. One of the axles is fused to the brake drum and I can't break it free. That is a minor inconvenience. The major inconvenience is the axles are 17 spline. I researched that and it was in 12 bolts for just a couple of years, 63-64. I was pleased to see I don't have pressed-on brake backing plates, they are held on with 4 bolts. 5-lug conversion axles are not available for 17 spline. I think I need to change out the stuff in this differential to get going with better condition and 30 spline.

[mr48chev]

That pin is plum as in plum worn out. I've seen worse though.

Your call on if you rebuild it or replace it.

[pjmoreland]

I've got an open carrier from a 1970 12-bolt that you're welcome to have for the price of shipping. It has the spider gears and pin. There's no ring gear though. If you're interested, I'll dig it out to take some photos.

[pjmoreland]

Here are some photos of what I've got. I pre-broke that bolt for you so you don't have to break it yourself. If all you need are the spider gears and the shaft, I can send just those to keep the shipping cost down.

[dmjlambert]

Thank you, pjmoreland, that is very kind. I would love for you to ship me the whole thing, I'll be glad to tinker with it and perhaps get this differential working again at least long enough until I can get a better condition one. I'll PM you.