I actually have another question before I have the mechanic take a look at the car next week. Sorry for all the questions - just want to be as prepared as possible!

The front passenger shock is likely shot... ok I can accept that. This means at the very least, I need to replace both front shocks. But I do believe the rear shocks are still OK and I haven't noticed any sagging in the rear. If this is the case, and my rear shocks are indeed OK, would it not actually be cheaper to replace just the two front shocks with the CATS Bilsteins (after labor costs)?

Eric - based on your assumptions, labor to replace front shocks is roughly an hour. Replacing the rear shocks is much more involved, so it would take roughly 3 hours. I can't remember my shop time costs right now but let's say $90/hour.

- Cost for two front Bilstein sport (CATS) shocks from Rockauto = ~$570 shipped. 1 hour labor = $90. Total cost = ~$660.

- Cost for all four corners Bilstein sport (non-CATS) shocks from Rockauto is ~$423 shipped. 4 hour labor = $360. Total cost = ~$783.

Any thoughts on this? Do you think there would be a noticeable performance difference between the new front CATS shocks and the old rear CATS shocks? One of the things that attracted me to this car was that the CATS shocks rarely failed, so I didn’t think I’d be worrying about this. Just wondering if that’s true, how “worn” do you believe the rear shocks actually are? Or would I be replacing the rear CATS for no reason...

Thanks!

 

I had rather similar experience with my (CATS, sport) front shocks - after the first time finding them sitting very low, I jacked each side up and put down; the front then sat almost as normal. However, after the next short drive, the shocks were down again.

If the mileage of your car is not very high, it is likely that the rear shocks are still pretty good so replacing the fronts only would be a good (economical) option. I don't think you will have any performance difference if your existing rear shocks still feel good/stiff when you try to bounce each corner. In my case, I replaced all four because they were all "sport" and I preferred to install "comfort" as my car is a Daimler Super V8. On an XJR, I would stay with "sport" shocks. In any case, the difference in ride comfort between "sport" and "comfort" appears to be rather small. I noticed only slightly more comfort after installing "comfort" shocks.

If you go with non-CATS all round, you will lose a bit on the stability (have more roll) on harder cornering and have a bit more "nose dive" on harder breaking. In normal driving, you will hardly notice any difference. On the other hand, you will have to deal with the "stability failure" message all the time due to disconnected CATS wires. It may be quite a task to find out what needs to be done to eliminate this fault message.

 

Almost assuredly the reason the shocks seemed to sit normal after jacking them up is the coil spring load pushed the wheel assembly inward and created the perception the shocks came up after being put back down. Any vehicle with a coil spring suspension has this happen when lifted off the ground. But simply rolling it back or forward a few feet, they will settle back to the alignment. This is especially noticeable on wide wheels with low profile tires.

I love my CATS, albeit an outdated system, it still performs well, especially on these heavy steel body cars. Thus the roll MS speaks of if you eliminate it.

 

Thanks for your insight, MS. Nice to hear from someone that had a very similar experience. My XJR has 94k miles, but the rear shocks still seem normal when I bounce the corners. It’s not low mileage... but it’s not high either.

Thanks again for the input and I think I’m leaning toward this repair option if my mechanic agrees that the rear shocks seem healthy.

About the suspension failure message when converting to non-CATS, I’ve read a few different threads on the forum that state you can unplug the CATS module and you’ll no longer get the fault message. I believe the module is located near the passenger footwell - easier to access if you drop the glovebox.

 

Very easy to solve; the suspension is controlled by an individual module, not in any way connected to the rest of the system.
Located passenger side, under the dash, just pull out the connector from the module and all is disabled, no message, and easily reversible.
Bit of a fiddle, but very doable.

 

Figured I'd try to capture my rear shock activity on video and see what you all thought, before I mentally commit to only swapping out the front shocks...

Any thoughts on the movement here from both sides? (P.S. Ignore the knocking sound - I believe that's the taper bearing in the driver's side rear hub assembly, but that's for another day)


Thanks!

 

The right one seems ok but the left one made a few bounces after you stopped pressing meaning not too good. Perhaps you can make another video where you press only once as much as you can - to see better how many times the body will bounce.

 

Thanks, MS - good advice. See below...

I think that driver's side rear is worse than I thought. I actually didn't think there was anything wrong with it before doing this. Wouldn't be the first time I was wrong!

 

Yes, the LHS one is not very good, bounces. You can actually compress the shock more, with the same pressing force, if you press right at the rear corner of the body (more leverage).

 

Thanks, MS. You’re right - much easier when pressing at the rear of the body. And further confirmed what was seen in the video. Will come back in a few days and update after the mechanic takes a look.

 

Hello again, all. Took the car to the mechanic today and he determined the issue is that my front springs need to be replaced. Shocks seem to be in decent shape but also suggested replacing those at the same time. I’m located in the US and I’ve tried to find the springs online... discontinued and they are pretty tough to come by! Any advice on where I can get them?

Part number for the XJR is JLM20424.

This site has aftermarket - I’ve reached out to them and I’m just waiting to hear back about shipping cost and speed... if they even do ship to the US.
https://m.onlinecarparts.co.uk/suplex-8311657.html

My mechanic recommended getting them from this site, but after trying to purchase them, apparently they won’t ship to the US. Most eBay items I found also do not ship to US. These are tough to find!
https://www.berkshirejagcomponents.c...24-c2x18742838

Any advice? Thanks!

 

Others might disagree, but I find it hard to believe that it is the springs ....

Yes, springs loose some of their length over the years, but it goes very gradual, and certainly not over a short time span of one night ....
Loosing a bit of ride height is mostly due to worn suspension bushings and the various foam parts, 2 inch in 1 time is shocks.

Does your mechanic have experience with Jaguar, cause he might not be aware of the fact that for our cars, the shocks do help in maintaining the ride height (as mentioned before).
Even here, on this particular x308 forum, there were several people who did not know this when my fronts broke down, you can see the various discussions in the link I provided.
Mine dropped 2 inches, and I was not sure when I replaced the shocks for new ones, but the car came perfectly back to its original ride height, and has been so ever since.

My 2 cents is still on failing shocks.

 

I guarantee you can find all the springs to your hearts delight here.... Car-Part.com--Used Auto Parts Market

But I concur with Eric on his assessment.

 

Thanks Eric - he does specialize in Jaguar (and Mini), but I think I’ll take it to another highly regarded indie Jaguar shop in town for a second opinion.

Highhorse - that’s an amazing resource. Sure enough, there were several listings for coil springs. Thanks for sending that over!

Will come back and update when I get the second opinion.

 

Don't waste time about the springs because there is nothing wrong with them (as Eric has also advised). Perhaps you can teach your mechanic about gas filled shock absorbers. The gas under high pressure inside acts as an "air spring" which works together with the coil spring. Neither of them can keep the ride height on its own, they work together. When the gas leaks out, the car will drop by about 2 inches.

 

Thanks, MS. I think it's time I switch mechanics...

I've had my XJR for about about 9 months. Haven't had any real issues come up so they've been fine for the typical maintenance items, but luckily with the help of everyone on the forum, it made me take a second look I believe I've found a much better Jaguar specialist in my area. Unfortunately (but probably not a bad sign), he's slammed with projects so it could be several more days before I can get the car in for him to take a look.

 

I will also add that my current mechanic charges 3 hours labor to replace both front shocks. Out of curiosity, I then asked how many hours labor they charge to replace the rear shocks, since I know it's a more difficult job. Also claimed 3 hours labor for both rear shocks... that doesn't seem right.

 

The front shocks are very easy to replace, you can do it yourself with a couple of spanners. The rears involve considerably more work but are still DIY, on the ground. If sending to a mechanic, make sure he is not the one doing it the first time. Some pics of my work replacing the rear shocks:

 

Thanks, MS - this is very helpful and a great idea! Looks like it makes it a relatively straightforward job.

Still a few days before I take the car to the new mechanic for a diagnosis. However, when I explained the issue to him over the phone, he found it odd the car was dropping in height "since there's no air suspension on my car like there is on the cars 2004 onward." I explained what you had said about the gas shock and spring acting together and he seemed somewhat accepting...

I take it to him first thing Monday morning and I'll see what he says when he sees it in person.

At this point, with the help of everyone's comments here, I'm sure its the shock absorbers. I am likely going to just buy the non-CATS dampers for all fours corners soon, have them installed, and move on to the next thing!

 

Will be interesting to see what he says next week ....

If you change the shocks, be sure you also replace the foam donuts in the rear (available from Rockauto), and the uppers on the front:

- I did my rear without replacing the donuts (they were stuck in the post that time), 2 yrs later I will have to do the rear again as they are slowly compressing, and lower the car.
- The front uppers are different between the NON cats and the CATS version, the non CATS version has a slightly smaller diameter for the rod.
Luckily for you, the non CATS uppers are cheap (Rockauto again ...).