Hello all. I have a 1990 XJ40. The PO had removed the self leveling rear suspension but as far as I can tell he didn't do the whole job. It looks like he only replaced the shocks and not the springs as the car sits really low in the rear and I replaced the rear shocks twice,(they kept wearing out), before I knew the springs were supposed to be replaced as part of the conversion. I'm going to get the correct springs, new shocks (again) but I seen that they have two different sets of spring spacers. 2.90mm & 6.55. Here's my question: If I get the correct height springs for non-leveling do I even need the spacers? If I still do need the spacers, which ones? 2.90mm or 6.55mm? Does it just come down to the ride height you want in the rear? Any help would be greatly appreciated.

 

The spacers are designed to level the car side to side and to fine-tune the rear height. They work in combination with the springs fitted to allow for slight differences in spring load length and it it isn't uncommon to find different spacers installed left and right.
In my opinion, the only way to know exactly what spacers to use (if any) would be to install the springs and drive the car to get the suspension to settle, then measure the height of the rear.
There is a formula for the spacer fitment. I can't remember it exactly, but the archive would have it. I think even one of my old posts on spring changes might have that info also - it's something like a 1/4" spacer raises the car rear 3/4" -but don't quote me on that - check the archive.

Also, this is the first time I've seen spacer thicknesses referred to in mm, generally spacer dimensions are quoted in fractions of an inch?

Larry

 

A thought that proved to be very successful for me. I replaced the rear suspension on my '90 Majestic with the springs and shocks from the XJ8.
Excellent result!