The rear of my US spec 2000 XJR is running about 42mm (1.65") low. I pulled the rear springs to check what was going on and it looks like the KYB rear isolators (MMD3565AA) have collapsed. They were installed a little over 3 years ago when I replaced the shocks.

The newer KYBs are now black while mine are the OEM yellow so maybe they've changed the materials but I'm still reluctant to go with KYB again. I see original Jaguar parts available but presumably they've been sitting on a shelf for 20 years so wondering if they are still good. The foam seems to deteriorate with age more than use. Rockauto is listing DEA / Marmon and Delphi alternatives for half the price of the Jag ones.

Anyone had good experience with either original Jag or other manufacturers?

 

Jaguar oem only for those rear upper shock mounts. 3 upper on each side.