XJ Rear Diff re-build

I am rebuilding a IRS for a hot rod (for a friend) and while I am used to E Type rears and some early XJ’s I have never met this type of bearing and need help, on the old ones they were two taper bearing and pre-load had to be set, this one has a one piece bearing so not pre-load (see photo, also where do these shims go ?

That’s my dilemma, do I just put it together, tighten the nut and forget it, or IF someone can point me at an article I would appreciate it.

Tanks in advance for help.


I would say the small shims are used to take up any movement between the bearings and the split tubes that space the bearings apart, the large shim(s) would allow you to take up the slack if the tubes were too long?

Inside the differential there is a type a bearing that the main bearing that is on the shaft is just the standard bearing and adjustment doesn’t really seem possible.

Must admit I’ve never met this set up before

Sorry I think I might have mis-read the question, I was assuming you were talking about the fulcrum bearings. Ignore my response.

There was an update there, and the old style bearings are NLA. The new bearing requires the spacer. Haven’t done the job myself, but I presume someone here can walk you through it.

no problem, I need all the help I can get, I have never met this before.

Hi Gary,
You are tackling most complicated end of the car, in my opinion. Tell me what exactly you are doing, or want to do, and where you found the bearing in your picture. I’ll see if I can help from there.


Another thought just came to me: what year IRS are you working on?


Unfortunately I do not know what it is from a friend of mine got it and asked me to rebuild it for his hot rod, I have worked on other rears with tapered bearings, but as you can see this is a one piece, that is the same as the one I took out.

This I purchased from SNG Barrett.

I am just replace the output shaft bearings and seals before it goes in the car.

Not sure if it will help you to help me but on my You Tube channel (jagvette1) you can see various videos I have made during this process.



There are no one-piece bearings in the S3 IRS and I’m pretty sure the same applies to the S1 and S2.

I will look at your video’s for a picture of the unit.

Here’s a picture of mine.