Opening up wheels/brakes/axles for projects, could use some parts selection help

[Roert42]

Hope that helps. From my shop manual on Ford 8.8.

I don’t remember every having the spring out at any point working on a track lock differential. Unless you need to get at the clutch packs.

I understand the 8.8 to be very similar design to the 7.5, just a little bigger.

 

[Lefty]

This is very clear. Maybe we should see if we can get a shop manual before we begin.

 

[lowspeedpursuit]

Other posters have already covered pretty much everything, but:

Pulling the c-clips by rotating the end-notched crosspin in place is impossible on a factory limited slip. Honestly, you don't want to pull the S-spring if you don't absolutely have to. Getting it back in is IMO the single most difficult step of working on one of these differentials.

If the crosspin moved a bit and won't go back in that direction, the opposite spider gear is slightly misaligned with the carrier, or the thrust washer that lives behind it has slipped out of alignment with the gear. If everything is perfectly aligned and the cross-pin isn't hitting the ring gear, it will come out in one direction or the other.

I'm supposed to be regearing my rear end before the weekend. If you're still stuck on the crosspin tomorrow morning, I'll get off my ass and take a video of pulling the c-clips, with the S-spring in place, using a magnet (albeit on a 31-spline 8.8, but everything will look roughly the same).

 

[Lefty]

By all means post this. These are the kinds of projects that make The Ranger Station a very special site. You might want to make this an entry of your own. I'm sure a lot of us would try this if we knew how.

 

[pjtoledo]

It looks to have the typical Snap On patented corners...

View attachment 77833

I looked at the Snap-On catalog, those are very expensive now.

maybe because they know how much it costs to dig out a rounded lock pin bolt.

 

[eightynine4x4]

Other posters have already covered pretty much everything, but:

Pulling the c-clips by rotating the end-notched crosspin in place is impossible on a factory limited slip. Honestly, you don't want to pull the S-spring if you don't absolutely have to. Getting it back in is IMO the single most difficult step of working on one of these differentials.

If the crosspin moved a bit and won't go back in that direction, the opposite spider gear is slightly misaligned with the carrier, or the thrust washer that lives behind it has slipped out of alignment with the gear. If everything is perfectly aligned and the cross-pin isn't hitting the ring gear, it will come out in one direction or the other.

I'm supposed to be regearing my rear end before the weekend. If you're still stuck on the crosspin tomorrow morning, I'll get off my ass and take a video of pulling the c-clips, with the S-spring in place, using a magnet (albeit on a 31-spline 8.8, but everything will look roughly the same).

Whew, what a sudden can of worms!
It's really amazing to have this community.

Earlier in the day I made this video for you guys (linked below) but didn't post it since you all had already answered some questions in it, such as possibly needing to dremel a gear or two to get the pin out.
But this video is still helpful just to be able to see the current status and also some detail of the pin. It's like 3 minutes, and I explain where I was at with it all, the biggest new concern being i can't get the damn pin back in place.
Now, i'm actually starting to think maybe i don't even need to get the pin fully out. Maybe i can just leave it dangling mostly out and that's enough clearance inside to get the C clips out.. WHILE those Z clips are still in too, hahahahahhahaahhah oh boy...

(Btw, those few white specs in the gears aren't metal shavings, just some crust from my gloves that i'll clean out. I haven't seen any shavings so far, except for on the drain/fill plug whenever I was adding oil.)

Dropbox

www.dropbox.com

 

[Uncle Gump]

I looked at the Snap-On catalog, those are very expensive now.

maybe because they know how much it costs to dig out a rounded lock pin bolt.

I don't remember exactly... but it was expensive 40 years ago.

 

[lowspeedpursuit]

Oh dude, if that's where you're at, you're golden. So the pin is hitting the ring gear; I guess the "thick gear" cutoff on the 7.5 rears must be lower than on the 8.8s, where that interference doesn't become an issue until 4.56 gears. But more importantly, the back of the pin appears to be clearing the axle shafts, so you can pull the c-clips.

If you haven't already, pull your wheels and drums. Leave the crosspin hanging out, then firmly press one of the axle shafts in towards the differential. You'll see the differential-end of the shaft move into the space the crosspin used to occupy, and the c-clip will come into view. Spin it with a pick or a screwdriver or something until the open end is either facing up, and the c-clip falls off, or if you have a magnet, until the open end is facing in towards the pinion gear, then you use the magnet to pull the clip off and out the front. Repeat with the other axle.

 

[pjtoledo]

try this video, he pulls the C clip with the Z spring in place.
on this video the Z spring has big enough holes for the C clip to pass thru.
does your's have a big enough hole for the C clip to pass thru?

skip to 18:30 in the video for C clip extraction

8.8 Trac Lok Rebuild, Fox body Mustang, Thunderbird, F150 - YouTube

 

[don4331]

OK, so I admit to learning something tonight you don't have to remove the Z spring to remove the axles. Thx, guys.

'course while I had the axle out to replace the one with damaged bearing surface, the axle bearing and seal, and had the Z spring out, I renewed the limited slip clutches, so I wouldn't have to do it again any time soon.

And that is my story and I'm sticking to it. ​

 

[eightynine4x4]

Were it not for the daunting seeming Z clip install, I’d be very tempted to renew the clutches as well. Is that all that’s involved when rebuilding / refreshing a limited slip? Just replacing some gears and putting all back together? I have been wondering about that.

Will be hopping back on this whole task in the morning, and hoping the pin really is clearing the axle shafts. Good call on that one! I hadn’t even thought of that! I’ll feel lucky if that’s the case. Gotta watch this c clip video and get learnt.

 

[don4331]

If you have the Z spring out of the way, refreshing the clutches is a piece of cake.

Pull the side gears, remove the old clutch discs/plates, install new ones* (pre soaked in friction modifier), reinstall the side gears.​

​

* I added one of the original discs to set it up a little tighter - which made reinstalling the Z spring even more challenging, but I do get 3 wheels turning when going gets tough.​

​

I'm betting Ford assembled the limited slip clutches, the side and spider gears, Z spring and cross pin into the carrier before mounting the ring gear and dropping it all into the rear axle housing. So you would have to grind ring gear teeth to remove the pin.

Grinding a tooth or 2 a little to allow pin removal, allows you to replace the cross pin with one that doesn't have any cutouts. (Small silver lining).​

 

[eightynine4x4]

On a side note, one of my brake drums is covered in surface rust. It does scrape off via fingernail, with a little work. I have a media blast cabinet so am thinking I could clear the whole thing off, or at least just the braking surface.
But am I vitally wrong about the braking surface? Glass bead blasting sure makes things smooth. But it won’t be the OEM surface. I guess maybe I try it out and then if I hear strange noises I just have to replace it.
The other drum is completely rust free. This is because that one is covered in gear oil!

 

[eightynine4x4]

Oh dude, if that's where you're at, you're golden. So the pin is hitting the ring gear; I guess the "thick gear" cutoff on the 7.5 rears must be lower than on the 8.8s, where that interference doesn't become an issue until 4.56 gears. But more importantly, the back of the pin appears to be clearing the axle shafts, so you can pull the c-clips.

If you haven't already, pull your wheels and drums. Leave the crosspin hanging out, then firmly press one of the axle shafts in towards the differential. You'll see the differential-end of the shaft move into the space the crosspin used to occupy, and the c-clip will come into view. Spin it with a pick or a screwdriver or something until the open end is either facing up, and the c-clip falls off, or if you have a magnet, until the open end is facing in towards the pinion gear, then you use the magnet to pull the clip off and out the front. Repeat with the other axle.

Success! The c clips were in fact accessible through the Z clips. Just had to rotate them then carefully knock them back with screwdriver on top and bottom and they fell down.
Next up is pulling the bearings and seals. Have the appropriate rental tools so we’ll see how it goes.
Then it’s on to cleaning of all parts, and doing the brakes.
As for reassembly, is there a stopping point/ridge for the bearings? Or do I somehow need to be careful how far I put them in? I’m imagining it’s got a stopping point, but I saw somewhere that there’s a version of bearings that sit at a different depth so as to not sit on the same worn spot of shaft. So now I’m thinking there might be some leeway and I could make a mistake with depth alignment.

 

[don4331]

Morning; We see light at the end of the tunnel.

The shaft location is locked by the cross pin/c-clip. You will need to push in far enough to install the c-clip, then pull out to put the cross pin back in place. There will be about an 1/8" play, but that is manufacturing tolerance. Might seem like a lot, but things shift significantly under heavy load and you don't want binding.

I don't think there is much variation on bearing location - they get seated in axle housing so you can't really move them in or out. And bearing width is fixed by specification.

The seal can and often is moved - so the new seal isn't in a groove from the old one. Because if it is in the groove, if might not be sealing.

One thing to watch for - if the new seal moves the sealing surface out towards the wheel, the axle might not be smooth (might be very rusty). In which case, it will ruin the seal in a few turns. You can try filing/sanding the surface smooth, but make sure you stay away from the bearing area (the case hardened layer is very thin and axle is quite soft underneath). There are also kits to sleeve the seal surface, to ensure it is running on flat smooth surface of at least OEM diameter.​