Jag Rear Questions

[Jim Harding]

A few weeks ago, the little noise from my rear got worse. After doing some talking to others and reading some internet postings, it appeared that the likely candidate were the stub axle bearings. So I drop the rear and drain the gear oil into a plastic pan that I placed a magnet in. Some fine metal particles show up. Not a lot; maybe enough to make a BB. And probably enough to grind away at the other bearings and gears..........

I also pull the right side stub axle and have a look at the bearings and races. Show signs of wear, but I don't have a clue of when or if the thing has ever been rebuilt. (I'm the third owner of this 26 year old car.)

From the picture below, it appears that the year of the rear is 69. The stub axle bearings used by Jaguar were ball bearings between the years of 69 thru 73, and the ones in my rear end are the ball type. These ball bearings are no longer available. Some internet postings say that the later '74-'87, '76-'87, and '89-'95 XJS tapered roller bearings are direct replacement.

I call Butch Capps and he confirms that replacement ball bearings are no longer available. He also stated that "some" of these vintage rears will not accept the later tapered roller bearings. He couldn't say which ones, but would be glad to rebuild my rear end if it is one that would accept the newer bearing. If it can't, the rear is junk.

I know that Butch is considered the Jag rear guru, and I don't doubt his knowledge or statements. I'm just asking if anyone else has ever been down this road, or knows someone who has that may be able to identify the rear by the info in the photo to determine if this rear can be rebuilt using the later tapered roller bearings.

If not, and the rear is toast, anyone know of a source of rebuilt rears or used ones suitable for rebuild? (Butch rebuilds for Unique, but does not stock rebuilt or rebuildable cores)

- Jim -

[Jim Harding]

Hmmmmm guess no one has ever had issues like this. Consider yourselves lucky! This has become a frustrating experience getting conflicting information from various sources of what I can do to repair this rear end.

Hey Alan, would you by chance have a rear end assembly gathering dust around your place? I'm getting to the point where a flange to flange replacement is getting more attractive. :-)

[pgermond]

Jim,

Fortunately I have not had to dig into my Jag rear, however, I know of several guys that have. This is where they go...... http://www.cwiinc.com/

No personal recommendations, just FYI

[JeepSnake]

Jim, you've probably already checked but -

Do the bearings have a number on them? I'm thinking that an industrial bearing supply house (Applied Industrial, for example) should be able to get the correct bearings, even if Jag and the car parts places have discontinued them. If there's a number of any type, they should be able to cross reference it via computer or book. It can then be verified by OD, ID, etc.

Even without a number, if you can find a "dang good ol' machinist" or machine design guy around, they can probably match it with a set of calipers and a Dodge (not the automobile company) bearing book. Or, if you can find an "on-the-ball" bearing sales rep somewhere.

I work with a guy (originally from Gadsden, interestingly enough) who has done mechanical design for 42 years, and he went through this ordeal on the wheel bearings for his '73 Mercedes convertible. Get this - Mercedes had the b**ls to GRIND the bearing numbers off the original bearings before assembly!!! That was their way of being absolutely sure that you came back to Mercedes for parts & service. So, my friend breaks out the calipers, micrometer, and bearing book, and just hunted down the bearings he needed as if he were building a new machine. I was/am in awe. (He's also an amputee who has built his own prosthetic legs for the last 30 years or so!!!)

(I'd tell you that I could do it, but the fact is that I'm just not that talented or experienced in the machine design realm; I've worked more with construction engineering.)

Anyhow, maybe this will help you out. Best of luck with it!

[Jim Harding]

Thanks for the tip Phil. CWI is one that I haven't spoke too, but have read several articles by them that state that the tapered roller bearing is a direct replacement. The cost of the new bearings are pennies compared to a new center section, so I might just pick up a set to see how they fit. The only thing that concerns me are the shims that need to be fitted to be with in their tolerances. I think the OD and ID of the bearings are the same, but the length is the issue. Need to do more studying on this.

Zach, I'm sure that somewhere on this planet someone has a bearing on their shelf that will slip in there with no problems. Like you said, the search will be more of an effort than the repair time.

Over the decades that Jag has produced this type IRS, it has made some little revisions to it that make hunting down the correct fitting part a nightmare for anyone who does not do this on a regular basis. You'll see references to early, late, style A or style B, series this or series that, and you're left scratching your head wondering what it all means. I think I'm up to four different part numbers for the stub axle bearing, and as many suggestions from vendors telling me that this is the one I need. This is why I'm getting to the point of just throwing up my hands and replacing the whole thing. I've never let something like this get the best of me, but for some reason this one is really kicking my butt.

[Naumoff]

Keep us posted Jim.
This thread will have good info for the future.
Unfortunately for you, it is happening to you.
Call me if you need a hand.

410-474-2701

[will butterworth]

is like the prostate, just a matter of time. Let us know how it goes cause we are all cousins in this business. Will-alabama

[Aggressor]

Our local NAPA store manager has matched bearing numbers for me and has never failed to produce the part within a few hours. Also there may be a bearings specific dealer in your area. Locally we had a distributor named Bearings Inc. Check the web and yellow pages for bearings companies.

-Geary

[weaver]

Jim, Maurice thinks he might have a set of bearings for your rear, call him when you get time.

Alan

[Jim Harding]

Thanks Alan, I'l do that tomorrow or Wednesday.... might be seeing the light at the end of the tunnel.......

And thanks Geary, I'll have to look into that lead if what Maurice has won't work out for me.

[spd4me]

Jim
I had a pre 80's cobra that I rebuilt the rear end stub axles on. I believe it had a 5 bolt pattern. I remember getting the numbers off the bearings Timkin. Some are made in China, Brazil, US, and England. Try Motion Industries, Inc. in Birmingham, AL. 205-251-3231. I also bought some jag parts from Terry's Jaguar Parts, Benton, IL 618-439-4444. You could also try Matthews Foreign Car Parts, Birmingham 205-251-5800. He has alot of real old stuff on the shelves. One problem I was having was oil leaking out through the shaft and not around the seal. There is a big nut that goes on to hold together. I filled the area with RTV before tightening bolt. Never leaked again. Wished I could rember more.
Bob

[YerDugliness]

I must admit that as a potential Unique builder, the use of the Jag differential is the ONLY concern I have. It's been my experience that rebuilding/replacing any "foreign" part can be quite expensive, as Jaguar parts tend to be.

Would anyone have an idea of replacement costs should something of this nature necessitate that?

Just curious.

Doug

[clayfoushee]

I must admit that as a potential Unique builder, the use of the Jag differential is the ONLY concern I have. It's been my experience that rebuilding/replacing any "foreign" part can be quite expensive, as Jaguar parts tend to be.

Would anyone have an idea of replacement costs should something of this nature necessitate that?

Just curious.

Doug

Doug, you couldn't possibly know this, but the original poster's (Jim Harding) problem is a bit "unique," no pun intended. Jim's Unique was built in 1982, and needless to say, his Jag rear-end lasted quite a long time.

The reconditioned Jag rear-ends used on more recent Unique's are done on model numbers with parts that are readily available today. It just so happens the parts used on Jim's particular now 25 year-old Jag unit are difficult to find today.

However, I can't remember the last time I remember reading someone needing to have a Jag rear-end rebuilt on this forum. Now if you want to talk about expensive, it's the big block FE that usually does people in. The Jag unit is the last thing you should be worried about.

Jag rear-ends are used on the higher end Cobra replicas because they are virtually identifical to those used on the original. ERA uses them, and even Kirkham uses their own knock-off of the Jaguar IRS rear-end design.

[YerDugliness]

Thanks, Clay. That's reasuring!!!

Doug

[JerryBP]

Except for the housing and axles the rest of the innards of the jag rearend are Dana 44 parts. (even the rear cover)