hi, Noticed today that my tires are down to the wear marks on the inside only and my tires only have about 3k miles on them.


SO excessive camber it is. I'm guessing my springs are toast, anyone know the specs on 1988 v12 ride height and where it is measured?

Just wanna be sure before I replace my 30 year old probably beat to hell springs that they are to blame

thanks

also does the XJ6, XJS, XJ12 share front springs or are they uprated for the XJ12 and XJS?

 

Cant remember the ride height spec, but it will be somewhere in my library.

It is measured dead centre of the front cradle (real easy access, NOT), and 4 1/2" comes to mind, and also including a full fuel tank, and cooling system?, and washer bottle??. Bizzare I know, but that bit I do remember.

I agree it could be springs, but check the lower wishbone INNER bushes first. Look from the front and observe that large washer on the pin. It MUST be dead centre of the eye of the wishbone. When those bushes wear that washer is off to one side and very obvious. The rear section is hard to see due to steering rack blocking the view.

 

Alignment and tire wear have to be evaluated properly. The tires will show wear that has to be interpreted. From my experience, the inner most (about the edge to 2 inches in) is TOE adjustment. The center of the tire to the inner edge is CAMBER adjustment. CASTER adjustment cannot be seen but affects the steering wheel centering while coming out of a turn. Some parts of the alignment can be adjusted out. Some parts of the alignment signify bushing wear which requires component replacement. Toe adjustment is easiest and usually does not require component replacement unless the tie rod ends are loose. I suggest having a competent alignment shop evaluate things and give you an idea of what to do from there. XJS' sit very low to begin with and have very little suspension travel.

 

Here's a bulletin that shows 6" ground clearance spec at the from subframe, FWIW.

Cheers
DD

 

thanks for the tsb doug.
Black x300 the tires are not worn feather edges or diagonal like excessive toe-in they are worn on the inside edge like there is just too much negative camber

 

The only other piece I can give you is to check your lower (or is it upper?) control arm bushings.

I had a similar problem with a previous XJS, alignment was not to blame, neither was the wheel bearings. I ended up changing out the control arm bushings, but the car was totalled before I could find out if it resolved my problem.

 

Whatever the body style the V12 version is always heavier than the 6 cylinder....so the springs will be longer and/or stiffer.

The Ser III sedan V12 springs would probably be very close to XJS V12 springs....but I'd hate to take a chance considering the amount of labor involved.

Cheers
DD

 

that is why i asked. Nearly everywhere I see springs advertised it says XJS XJ6 etc as if they are selling it for all of them

 

Yeah, I've seen that before. I'm always suspicious of parts listings that appear to have an overly-broad application, like 'Front Spring, all 1976-1996 XJ6 XJS XJ12'.

Over my umpteen years on Jag discussion forums I've read many reports from those who have changed springs and ended up too high or too low. For that reason I've always suggested not replacing springs unless it was absolutely necesary.

However.....

Even the true OEM choices were relatively few in number because, rather than having lots of different parts numbers, Jaguar used spring spacers for ride heght trimming

Cheers
DD