Just a quick question regarding the replacement of the original front shock absorbers on a XK 4.2 N.A. 2007 with XK 5.0 black body with purple spot Bilsteins, are compatible considering the 4.2 are two stage(soft/firm) and the 5.0 are variable rating? FYI I have tried the new shocks plugged into the shock connections with the car idling with no visible instrumentation warnings and no logged faults on icarsoft code reader.
If these shocks can be used I will swap over the original mounts and springs, these new shocks are genuine Jaguar which picked up ages ago for £170 for the pair a real bargain.

Paul

 

Won’t work. Been there, tried that. The 5.0 shocks will remain in the ‘hard’ setting.

 

Thanks for the prompt reply, strange that the part number on Bilstein website shows the same part number for the 5.0 and 4.2, there is always the option for having my shocks rebuilt by Bilstein Uk for £100 +VAT I suppose.

Paul

 

That’s been a source of confusion for a long time.
Good luck with that. I think I’ve read that our shocks can’t be rebuilt. If you find out otherwise, let us know (hard to find even good used 4.2 shocks).

 

Yes I'm considering getting in touch with Bilstein here in the UK to enquire whether a rebuild is possible, I will post on here what the result is.

Paul

 

life has gotten in the the way of my needed XK updates...I will be replacing the shocks most likely with the ones from. BC Racing or low mileage take offs.
This just occured to me, since I generally drive in S in order to firm up my XK's suspention, just how hard is hard!
If it is the same as my firm in the XK. I'm good with that. Can you give any insight?
wj
2008 XK

 

I also often drive in S, which gives a nice exhaust note blip on the downshifts. I don’t find the ride quality impacted by S mode as much as it was with use of the 5.0 shocks. My impression was that the front end became ‘bouncy’ and wasn’t absorbing bumps at all, rather unnerving.

 

I've decided to replace the front and rear shocks with some used items from a breaker who is breaking a 2008 XKR, £225 delivered.
The reason why I decided to replace the original shocks is although the shocks show no signs of leakage, I found that there is a rattling sound from the front shocks only when driving over slightly uneven surfaces never over rough or undulating ground.
​​​​​​Even after thorough checking of all other suspension components and replacement of top shock mountings the noise still persisted, suggesting an internal fault in the shocks, used parts seem to a cost effective solution to this problem hearing in mind the ridiculous cost of new items.

Paul

 

Transmission “S” mode has no effect on CATS mode.

 

Used dampers... that's a first.
I think you'll find you may also have worn bushings that present themselves as a knocking noise when hitting the bumps.
Sway bar bushings??

 

Yes they are used off a low mileage XKR, I reckon that because these shocks are not leaking and are robustly built so will hopefully solve the rattling noise and provide good service for a while yet. As for your suggestion for the sway bar bushing I've replaced these along with the drop links, I can't find any play in any other bushing and the boots are in good condition on all ball joints so leading to the conclusion that is shock absorber related.
About 2 years ago I was driving through narrow village road at 30 mph and had to mount the kerb to avoid a speeding van which led to a CATS warning light on the instrument cluster, this I cancelled and it never returned but I think this led to internal damage in the shock.
Because I try to do all my own repairs and servicing and have had shock absorbers off this car before, it's worth my while to try and solve this this particular annoying rattle unfortunately as stated previously I have 2 expensive 5.0 shocks left which will be stuck in firm mode if I attempted to fit them.

Paul

 

@Paws4thought did you contact Bilstein as you noted above?

 

Those 4.2 XKR shocks will be a bit stiffer than your original 4.2 XK shocks, but at least they will work.

 

Sean, yes I contacted Bilstein Uk unfortunately the service manager was not available so I spoke to sales rep who suggested the shocks would be serviceable if the top of the damper was capped but not if the body was simply crimped. Looking at the photos of the genuine Jaguar shocks online all appear to be pressed on cap so should be able to be refurbished.

Paul

 

Hi, I spent a long time trying to sort this out several years ago after my 2007 XK failed the MOT with a leaking shock absorber. I tried fitting Bilstein dampers which were supposedly for my car. Once fitted at great expense the suspension was rock solid. After a lot of investigation I discovered the solenoid resistance on my original dampers was different to the new ones, It appears the early version of CATS which was only fitted for a couple of years will not work with the later version due to the coil resistance issue. I was unable to find a set of new dampers so I had to go down the second hand route and managed to source a a good low mileage set which once fitted thankfully worked perfectly.
I'd imagine getting used dampers now is getting very difficult though I believe there are some companies that offer a refurbishment service.

 

you are mistaken, my XK (maybe that is the difference you have xkr) bounces and wallows in D, in S it is much tighter.
wj

 

It’s been a frequent question in the past and been confirmed both by the user manual, Jaguar and others that the “S” button’s ONLY for the transmission’s shifting characteristics, the transmission’s not connected to the CATS system. This forum and others can confirm this for you. With the 5.0 litre cars, a button was added for the suspension allowing driver selectable suspension modes instead of only automatic.

 

First, I do respect your opinion. Second, regardless of what you have stated my 2008 Jaguar XK convertible when placed in S mode will:

Lean far less going into turns

Not float over undulations in the road surface

Respond quicker to L-R movements.

Everyone can make their own decisions as to whether I’m out to lunch or not but after 40 years in the exotic car business I do know when a car leans, wallows, floats and when these driving characteristics change. I’m not referring to slight variations either, even my GF who doesn’t pay much attention to my driving any longer has mentioned how the car is much smoother when in D, ‘in S you can feel every rock and pebble’.

I think anyone can surmise that if the road feel changes when in S then there is a change to the shock valving.
If your ever in my area we can certainly go for that ride that will prove my statement and follow up with a BEER&BBQ.

FWIW, I’m now off of my soapbox.

wj

 

Jim,

I agree with what you said above. My 67K miles 2009 XKR has a distinctly different feel when in Sport mode. Much less bounce than the standard D mode.

Agree on the BBQ and suds!

 

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