Thread: Stuee's 101 Rebuild

I would get it pulled apart and everything in a molasses bath for a while. That will clean everything up and show you jaw much (if any) damage there is. Apart from new bearings, I think it would be fine.

Get it cleaned up now, then worry about getting it back together later. You don't want the rust to progress any further than it is.

I if was mine I would.
drop the diff centre out ( you will not need a spreader, just a pry bar and lever the centre out.)
To drop the centre out you need to disassemble the front brakes, remove the C/V housings which require removing the 2 upper and lower bolts on the C/V housing which hold the C/V into the swivel bearings, remove the C/V housing wiper seals( bolts on around the inside of the C/V).
The whole C/V housing will fall away exposing the C/v joint itself.
Pull the C/V out of the axle tube and inner diff with the drive axle.
Doing the above removes the drive axle from the diff centre so it can be removed.
I found a old pillow a good thing for the diff centre to fall out on to.
It sounds difficult , but is easy when you get into it.
Doing the above is a perfect time to fit the disc brakes.
I suspect the bearings will be shagged.
The diff centre carrier bearings are straight forward, but the pinion bearings will need looking at , that job is abit more difficult.
Pray the crown wheel is OK as the replacement is abit pricey....but advailable.
Looks if the moisture that has been in the diff housing is though storage?????
The 101 diffs do like to suck in water due to the small breather banjo bolt that blocks up and the leaky C/V and diff seals.
Clean up the inside of the diff abit and bearing blue the gear contact pattern, as the marks you get before dropping the centre out are the same marks you need to get on the reassembled diff.

Excellent time to do a ARB locker too.
For pics go though the old threads and find my front ARB locker fitting thread.

I only needed a diff spreader because I was taking the diff centre in and out a lot to set up the diff lockers.
Garrycol should be helpful as he had some problems with rubbish in one of his diffs.

Thanks for the advice fellas. For the time being I soaked it all in WD40 to displace any water. As I turned the axle I did notice a reasonable amount of condensation start to bead and run. I assume it is only from storage because where there isn't rust it looks immaculate.

I'll pull it out and get it cleaned up, in the mean time I need to wait till next pay for the bearings (damn weddings - still haven't been able to buy the inner bearings for the hubs either). I'd love to do an air locker now but just don't have the money.

Replacing the breather fittings with some straight through ones was on my to do list. Was going to do it after inspecting the centre with the cover off. Glad I did find the problem now before the disc conversion, otherwise I'd have to pull it all back out again

Ill come back and ask you some more questions about it Ron when I come to it. Specifically the bearing blue, is this just to see how the teeth currently mesh? If so I dont know how I would adjust it if I put it back and it wasnt the same. Would pull it back out and make it 2wd until I could send it to a specialist Or is that only applicable if I pull the pinion out too?

If I was buying it I would steer away from it or want it fixed before paying but If I owned it it would be WD40 and more WD40. Give it a good clean out and see what it looks like. It takes a bit for rust to set into bearings, you might get a discolouration but it will take a bit to get pitting happening due to rust. I would keep the thing going until funds are available after doing the other bits you want done.

Just another thought on cleaning it up. As mentioned, molasses is very good. Why not just pour a molasses mix into the diff housing and let it all soak in there or a while. You have to pull it apart at some stage, so you could rinse everything then...

Originally Posted by bacicat

Just another thought on cleaning it up. As mentioned, molasses is very good. Why not just pour a molasses mix into the diff housing and let it all soak in there or a while. You have to pull it apart at some stage, so you could rinse everything then...

Not a good idea.
When you take the bits out of the molasses solution, you have to clean them real quick. This might prove difficult in the axle housing.

The idea to bearing blue the gear teeth before disassembling the diff is to see how well the diff teeth are in adjustment and how they are wearing.
A diff which has been quiet and working well, but is found to be not set up right ( the contact pattern not totally correct) would most likely be better off being set up the same on reassembly, as if it was set back to factory spec gear contact pattern it would come noisey as the gear teeth have worn in a certain way previously.
If the diff centre carrier bearings are just only replaced, it would be most likely nothing would change with the diff set up and contact pattern, bearing blue on reassembly will confirm this.
Crown wheel and pinion backlash should also be checked with a dial guage too.
Yes true diff set up is best left to people who have had experience in the field as it can come expensive if you get it too wrong.


I may add the big gripes about ARB air lockers leaking internally is usually though improper set up of the diff concerned( a lot tend to be fitted by the owners) and any play in carrier bearings( preload) or incorrect set up ,etc will result in leaking O rings.

Not too much to update. Just though I'd put a bit up here after looking at bacicat's thread.

Finally have all of my disc brake conversion after a number of phone calls and emails to the UK. The quality of the kit does look good.


Don't know why its got "UK only" written on it. I suspect I hounded them enough so that I got the next kit off the assembly line.

I've progressed further on the battery base and fuse panel location:



Not entirely happy with my makeshift grommet so will keep my eye out for a better solution.

Keeping relays in the same place, only the new type and more of them:


The dash part assembled so I can plan out my wiring. You can see my cheap ebay o-ring around the left hand gauge. I couldnt find any square cut o-rings and the vendor sent the wrong size so this will do until I get a better one. I cut one o-ring in half so it has a u profile instead of a circular profile to act as a seal between the glass and the retainer ring on the left hand gauge as well. For whatever reason the right hand gauge rubbers were in good condition so I have re-used them.


Back diff looked good. Oil was milky but condition of the doff was good overall:


The front diff is looking better after flooding it with WD40 all week. It looks to be washing the rust away and the urge to be lazy is kicking in (at least till after its on the road). A catastrophic failure will mean it would only make economic sense to put an air-locker back in wouldn't it??