Does anybody have a diagram of the TUPY 80-18-007 rear differential? I have to change the pinion seal and does anybody have advice on how to do it?

Thanks

 

OK an add to this. 91 XJ6 It seems the TUPY diff has typical parts and the oil seal I have will fit the pinion shaft . The driveshaft does not have a universal joint on the input side. There is a hard rubber donut. Can it be removed without moving the middle drive shaft bearing? No drawings I have show this or how to drop the driveshaft to get to the pinion oil seal. I need advice.

 

All I know about this is that you have to mark the bolt positions and reassemble as you found it to keep things balanced. BTW, the "donut" is known as the Jurid coupler.

AFAIK, my diff isn't a Tupy, but I have a 94. I thought all the XJ40's had Salisbury diffs?

Look through this thread for some tips ...there is also a link in the thread to a French owner's site showing the how-to, lots of pictures there.

https://www.jaguarforums.com/forum/x...others-274735/

 

Thank you Lawrence. That is exactly the help I need.

 

Hi sweetpeas,

It's always helpful to tell us the year and model of your Jaguar so we can provide the most accurate replies. If your car is an XJ40, the differential is most likely a Salisbury 15HU unit made in England by GKN under license from Dana. I think TUPY is the company that made the housing castings.

Before you detach the Jurid or flexible coupling from the differential, it's prudent to make marks on the coupling and differential flange so you can reattach the parts in the same alignment. It may not be a problem to reconnect them in a different alignment, but some owners have had driveshaft balance problems after reassembly, so you want to minimize the risk.

You may need to detach the driveshaft center bearing for clearance to pull the driveshaft away from the differential. If you need to do this, carefully scribe or mark the positions of the bolts and center bearing mount so you can reattach it in exactly the same position, or you may have driveshaft vibrations.

As Larry mentioned, before you loosen the differential input flange nut, use a center punch to mark the nut and pinion shaft so you can return the nut to exactly the same position when you torque it. This determines the preload on the pinion shaft bearings, and if it is too loose or too tight you will have serious problems.

When the pinion nut is installed, it is torqued to about 500 foot pounds to compress a "crush sleeve" and set the proper pinion bearing preload. Preload means there is no end-play at all in the shaft and bearings, so if you can move the flange in and out after you reinstall it, either the nut is not tight enough or the pinion bearings are worn (very common).

At the link in my signature are some of my photos at the Jag-Lovers forum, and I have one or more albums on rebuilding the differential, which may have some information that will be helpful as you replace the pinion seal.

If you can, please take some photos of the job and post them here so others can learn from your experience.

Cheers,

Don