Rear Suspension query

[mark229]

My lovely X100 convertible (year 2000) 127K miles , has jitters on the rear suspension..

I have replaced the CATs shocks all round for much newer and stiffer 65K units..

Most bushes look and feel ok..

However, can all bushes be changed bit by bit, without dropping the whole subframe?
If so where should I start?
It just seems a bit bouncy/jittery at the back..CATS all work properly..

I just dread the thought of dropping the whole subframe!

[mike020150]

To better understand the issue, can you describe what you mean by "jitters"?
Soft/old bushes result in suspension knocks as well as poor straight line stability and excessive tyre wear. Genuine Jaguar bushes are compromises to achieve good stability and low noise transmission. Has someone already replaced the Jaguar bushes with firmer poly versions which, although more precise, will transmit more road shocks through the car? Similarly, poor suspension alignment can produce a harsher feeling car. Mike.

[mark229]

OK..

Thanks for your reply!
I believe the rear to be 100% original.. I have done the Anti rollbar bushes and drop links..
Also when changing the rear shocks(with new lower bushes), the droping the subframe on one side, change shock then the other side, along with the top bolt on the rear frame..The bushes looked actually very good no slop etc.
The jitters are.. on a smooth flat road lovely, it seems to me that the rear feels sloppy on large bumps etc.
She drives straight, no sideways jumping etc. on the track day this year, very stable even at good speeds..
My thoughts are maybe I am expecting way too much from the old girl!
I have nothing to compare as aside from an MGF, my XF Sportbrake, which at 100K, is still very smooth!

It could be I am being over critical, with the normal scuttle shake exagerating problems, that may not exist!
Most passengers say how smooth and stable she feels.. with brilliant handling!

The rear tyres are actually rather old and worn, maybe too hard as aged, so could be a factor, I run tyre pressures a 29 to 30 on 18 inch rims!
I suspect I need to feel the ride quailty in a known good XK8 convertible!

[mike020150]

A comparative ride (preferably in a car with decent tyres!) sounds like a good idea. Mike.

[M100TWO]

When you was working on the suspension did you tighten everything up with the suspension at ride height?


John

[mark229]

Hi again
Yes, all bushes etc are tightened at ride height! A very valuable point
I have recently added a strut bar at the front and that has(much to my surprise) smoothed out the front further..They also do one for the rear, strenghtens the area from front to back of the axle area, in addition to the light and small Jaguar originals..I suspect this will help reduce quiver!!
https://ultraracingshop.com/products/ul ... s=e&_v=1.0

I am convinced maybe wrongly, as the shells age they do weaken a bit, especially following 24 years and some welding.. Thoughts please ?

[mark229]

I notice the M100TWO..My XK SB, is M100MNG!