I noticed that my '96 2+2 which I have been recently working to get in top-shape has only just recently started to show some wear on the inside edges of the rear tires. It's always wore all four tires very evenly and for many miles in the past so this is something new.

I took it to get it aligned and they noticed the wheel will move slightly in and out on each side, what appeared at first to be a wheel bearing but the shop said the wheel bearings and the U-joints seem nice and tight. That this movement is actually because the axle shaft serves as the upper control arm and the shaft is moving in and out of the rear end a bit... A little on the right side, more on the left side. It is also just starting to show some signs of leakage around those seals.

So on a trip earlier this week I stopped by a small Jaguar shop recommended to me by someone at one of the Jaguar Parts Places we all know. For now I wont mention the name of either place.

Anyway, they said the movement on my right side is actually within specs though only just barely and the movement on the left is a bit excessive so a little out of spec. So I was expecting them to tell me I needed shims inside the shaft and new seals. Instead they started telling me that I needed to just buy a whole new remanufactured rear-end, something that of course is offered by their friends over at the Jaguar parts supplier down the road.


This car drives great, the tire wear on the inside edges is only just barely noticeable (and this is at least 30k if not close to 40k miles on the tires), and the seeping from the seals is only barely noticeable and never shows low when you check it, and when I changed it early last spring the fluid looked nice and clean (no excess metal particles, etc). There is also no noise or odd sounds coming from the rear end. As my local shop said the U-joints and wheel bearings seem nice and tight. Everything does except the small amount of excess in/out movement of the shaft into the rear end mainly on the one side which I always thought shims was used to correct.


So, my question is, has anyone heard of changing a whole rear-end in such a situation, or does that seem kinda excessive?


Does it sound kinda like this shop maybe trying to sell me over 3k worth of parts sold by their friends down the road along with a bunch of labor from them over something that would normally be fixed with shims, new seals, and an alignment?


Rear-ends on these things is one thing I admit that I don't know a lot about other than I never cared for the design where the side-shafts do double duty as your upper control arms. They ride and handle great but I always wondered why Jag didn't just use a 4-link setup like so many performance cars which would provide the same ride/handling and be less strain on the rear end and axles and easier alignments.

 

Look at item #24 in the illustration:

http://www.jaguarclassicparts.com/uk...nit-components


What the shop is referring to, it seems, is excess in-and-out movement of this output shaft. Since the half-shaft/axle-shaft is attached to #24, it moves in-and-out simultaneously. Since the half-shaft acts as a upper control arm, as you say, this excessive in-out movement alters the geometry of the wheels/suspension.

I had the same issue, but far worse, in my '88 XJS. I noticed weird behavior when entering a corner at speed. As the shaft moved, the wheel camber shifted...thus the strange behavior. I ordered and installed a rebuilt differential and the problem was solved.

You might thinking of the camber adjustment shims. Those fit between the output shaft and the axle shaft. They won't remove the free play that is occurring in the differential...almost certainly due to worn side bearings

Cheers
DD

 

That shop is actually the ones who was talking about shims inside there so I'm not sure what they meant then.

But anyways, Wouldn't new side bearings solve the issue if that's what's actually worn?
(No doubt a lot cheaper than a whole rear-end)

 

Yes, much cheaper but only if you do it yourself. If you pay somebody else to pull that rear end and fix it up it would be scary expensive.
From memory jag moved away from shims in the output shaft bearing assemblies to collapsible spacers.

 

On many differential the side bearings are adjusted or 'set up' with shims during overhaul...but not for taking up fee play miles down the road.

In any case...as far as I know....you side bearings are set-up using a 'crush sleeve' or 'collapsible spacer'....which is a 'one time use only' thing.

Rather than a full overhaul, the output shaft assemblies can be removed and new bearings, seals, and crush sleeve installed. Yes, cheaper than a full overhaul....if the wear is isolated to those bearings. Worth investigating, I'd say. Coventry used to, and perhaps still does, sell rebuilt output shafts for about $175 each or so, as I recall

Let's hear how others have tackled the problem.

Cheers
DD

 

Yes I noticed some sellers (JagBits for one) offers a "Differential Rebuild Kit" for $299 described like this;

DIFFERENTIAL REBUILD KIT, FITS 1976-1997 XJ6 AND 1976-1996 XJS Includes the stub axle bearings and seals, carrier bearings as well as the pinion bearings, crush sleeve and seal, and all of the seals, collars etc to rebuild your differential.


Which sounds much better than $2400 for a whole rebuilt Differential. Assuming this kit has everything needed. Either way I'd have to pay someone labor to put it in and set it up. The place wanted $2400 for a rebuilt diff and then the shop wanted about $1100 to install it. That's way out of my budget. If the $300 kit would do it, I estimate (from past experiences) that my local transmission/rear end shop would probably charge me about $400-$600 for installing it. So $3500 vs $900 if the kit would do it, one is in my budget, one certainly isn't. But that is of course IF that kit really has everything needed to do the job properly (other than the fluid, etc. of course)

 

My opinion is that you don't have a problem severe enough that you need to do anything. Just keep an eye on it and check the lube if it leaks. Two years ago I had the bearing and seal replaced on my right side output. The seal was leaking enough that I did this but I could have just watched the lube level and topped it off when needed.
As far as tires with 40k miles having a little inside edge wear, also not severe enough to warrant a lot of expense. That said, If you are an owner that has deep pockets and want the car to be as near perfect as possible, go for it.

 

Thanks for the advice and I know what your saying and I certainly don't have deep pockets (carrier Army). I just really don't like the idea of putting on new expensive tires only to have them immediately start wearing on the inside edge, and I also don't like the idea of ANY leaks on any vehicle. So I want to fix it, I just don't want to get taken by someone wanting to sell a complete expensive rebuilt diff when I may only need a kit with new seals and bearings, etc.

 

The Crush washer is on the pinion and is used to set pinion back lash. The output bearings to hemishpere are set using shims, a real PITA to set as the hemi needs to be installed and torqued up measure the backlash, pull it all apart again and add shims, if your lucky and measured accurately you won't need to pull the thing apart again to reset the shims.

 

You will most likely not need a complete rebuild. Jaguar diffs are very hardy and quite strong.

What you will need is a bearing and seal kit. May as well replace all bearings. This will require the the diff to be removed completely disassembled and re-assembled with the new bearings.

Hardest part of the whole exercise is getting the diff out of the cage as almost everything bolts to the diff. It may be possible to do this with the diff still in the cage, not sure maybe someone has done this and can chime in.

 

Collapsible spacers are also used in the output shaft assembly. The removal and replacement of the assemblies has no affect on the diff settings. Pre load needs to be set on the output shaft bearings before the assemblies are fitted to the diff.

 

Baxtor is correct. The ring and pinion bearings are a different set-up from the output shaft. These bearings are pressed onto the shafts and installed on the diff and secured by bolts on the flange.
SouthernGypsy, I haven't noticed your having mentioned the mileage on this car. I did see a member say these diff are quite strong and yours may not need such extensive work. A new bearing and seal on the shafts would probably be all that you need. 100,000 or less miles should not be a problem.
Cheers, RagJag

 

Right. Item #2 in the illustration below....



I was referring to item #26

Final Drive Unit Components - Parts For XJS from (V)179737 to (V)226645 | Jaguar Heritage Parts UK

Cheers
DD

 

Get with your local Jaguar Club ( or nearest ), they will either offer a place for less money or get with you and fix the problem. These Club members know where to save money, I have done work on their cars where I live and they know how to save their cash.

 

I haven't heard of a club around here yet, have meet a few individual owners but haven't heard of an actual club so far. Is there a list on the site somewhere of club locations? I'm in North-Central Arkansas; 1.6 hours north of Little Rock, 2.2 hours north-west of Memphis, and 4.7 hours south-west of St. Louis, 5.6 hours from Nashville, and 6.5 from Dallas. I haven't heard of one in Arkansas or even Memphis (maybe there is and I've just never heard of it), St. Louis, Nashville, or Dallas might be the best chance where one would be located though that's a pretty good drive to any of those. It would be nice though because while the transmission/rear end shop here is willing to try (and are friends of the family so reasonably priced) they are mainly transmission specialist. They don't really do many rear-ends and admit they have never done one designed like this before.


If there was a place that would do the work at a reasonable price and can get it done in a day or two I would not be against buying the parts and getting them all collected together, making an appointment, and driving there and staying in an economy motel for a night or two while they did the work. Especially if it was a location where there was other things to do while I was there.

So if someone knows of such a place please chime in.

 

Got ya I didn't have to rebuild this so never even looked at it. I'll have another drink now

 

The stub axle bearings aren't too difficult to sort out and can be removed in vehicle if you are keen.
I would make absolutely sure this is your problem though. If your tyres immediately start wearing, it still suggests an underlying alignment issue.
If the stub axle bearings are OK and just worn (very likely) it is absolutely fine to either reshim or reset preload by crushing the collapsible spacer more. The collapsible spacer can be reused if reducing it's size (adding more preload to take up wear) as it is merely crushed a bit more to reset the preload. However, if your stub axle seals are leaking, you'll need a new crush sleeve to get to the seal anyway.
The beauty of the stub axle assembly is it can be removed and reconditioned or repaired as a unit. I wouldn't dive into the differential unless there was another pressing need like a leaking pinion seal.

 

They said my pinion is showing some signs of seepage but I had assumed that could simply be changed from the front without going into the diff itself.

 

Right.

Opinions will vary on the wisdom of replacing the pinion seal unless it is absolutely necessary. Mine is "Don't do it".

Unless the shop reassembles everything to the ** exact ** pre-existing settings/torque, the pinion setting will be thrown off....with pinion bearing failure quite likely. Even a well qualified tech can flub this up, possibly without really realizing it.

Years ago, when I was in the repair business, I did an informal warranty repair study researching the history behind 50 differential overhauls. I found that [something like] 70% of cars needing a diff overhaul had the pinion seal replaced within the last 12,000 miles.

Others will chime in.

Cheers
DD

 

I pretty much agree Doug however, my car was knocked back on a roadworthy cert. a while back on the basis of a seeping pinion seal so it needed to be done. l did not find it too much trouble. Getting old seal out was not easy but recording nut position and resetting preload settings is detailed in the manual and no trouble with diff since.