Hi everyone,

now I'm at the point where I need to go right or left with my 2006 XJR-s air ride.
The symptom is, that it makes noises when I go on a little bumpy road (especially at low speeds, and when little wight is on the back of the car - downward slopes, etc), and it sits on the wheels if I leave it for about two nights.

The dealer said I need to replace at least the two in the back, and let's check what happens next. Of course they wanted a fortune for the 2 shocks, so I started to look around, and that's the point where I got confused.

First I found Arnott's products, which are available here in the EU also, but they does not respond to my questions, and I cannot really find an answer, whether their renewed shocks has the shock part replaced, or it remains the same, and they only renew the air bag part... In this case therer is no guarantee that I will not have problems with the shock part anytime soon. Their new, self made one will turn off CATS, so that is not an option either.

The second option is to buy Bilstein shocks, but there is another problem with that also. They state on the product page that their shock is for sport AND comfort suspension. Which sounds interesting to me, as Jaguar has two types, with to part numbers (green and red dot). So I'm not really sure about I can buy these, especially if I only change the rears. Does anyone here has some experiences with these socks in an XJR?

The last option is of course to buy the genuine Jag shocks, but I would like to know for sure that I have no other options.

Any advice or experience would be highly appreciated.

 

Hi Hooshee,

From your description, I would suspect a few things:

1. You may have some failing suspension bushes or other loose components that are making rattling noises over bumpy roads. I do not recall other owners reporting noises from the air shock absorbers, but I suppose it is possible.

2. You may have one or more air leaks in the air suspension. You can check for leaks by spraying a mixture of soap and water on the air hose fittings at the top of each shock and on the valve block and air reservoir, which are mounted in the boot/trunk under the spare tire. If you see bubbles, the fitting is leaking and needs to be corrected. Replacement brass compression fittings or "olives" are available and inexpensive.

3. It is also likely that the piston ring seal in your air compressor is worn and no longer pressurizing your system as well as it did when new. Forum member Andy Fulton (bagpipingandy.com) offers a replacement Teflon seal kit at an affordable price, and replacing the seal is not difficult.

I would suggest you get a second opinion from another repair shop and ask them to inspect your suspension bushes for signs of failed bushes or other causes of the noises you are hearing.

Cheers,

Don

 

Hi Don,

thanks for answering. Actually the whole suspension was inspected several times, and no loose bushings or components. I triple checked it at least, that's why I'm thinking about the shock itself, however, the computer check of the absorbers themselves. But regarding you point three, I give it a shot.

The dealer said they have checked the leaks, but I think I will do it myself again, just to make sure. Are there any fittings near the shocks also?

Thanks, I'll check that seal kit, maybe it solves my problems

 

Bought the kit, thanks for the suggestion, I'll get back with the result

 

The air hose fittings on top of each front shock are easy to see. There are similar fittings at the tops of the rear shocks, but they are more difficult to access. The air hose fittings on the valve block and air reservoir tank are easy to access under the spare tire. Spray a little soapy water on each fitting when your air suspension is fully charged up and watch for bubbles, which indicate a leak that needs to be addressed.

Search this forum for many posts on air suspension leaks. Our member abonano is one who has posted some good specific information on the air hose fittings.

Cheers,

Don

 

Even if only one air spring is leaking, the car will eventually settle onto the bump stops due to the self-levelling system which tries to keep the car level even when the car engine is shut down and the car locked. After a while it goes to sleep, but wakes up every 24 hours and re-levels the car. However the compressor is not used just the remaining air in the reservoir, so basically, if there is a leak, the car will end up just sitting lower and lower.

You haven't told us the mileage of the car (total kilometres), but these air springs are fairly long-lasting, being made by Bilstein, especially the shock absorber, but the diaphragms can end up leaking a bit, as can the connections at the top of the spring units. There have also been reports of air leaking slowly out of the top rubber seal. Any air system with high pressure generated in the system will eventually start to leak a little bit, it is when the 'little' becomes 'a lot' that you have a problem. Have you had the fault codes read ? Was one of them C2303 ?

As for noise from the rear on bumpy roads, it indicates some wear in the suspension bushes somewhere. My money would be on the lower bushes of the air springs, or the anti-roll bar link and roll bar bushes.

Have you checked the Bilstein units. When ordering you may have to specify whether you want Sport or Comfort. Frankly it doesn't really matter if you fit either, the car will still work and the ride height will remain the same. However, all four have to be Sport or Comfort. You need to check what is actually supplied. Here are two UK suppliers

Air Spring - C2C41347 | Jaguar XJ 2003 - 2009 | Jaguar | British Parts UK

Jaguar Partno_C2C41340#_AIR SUSPENSION DAMP X350 >G35210 REAR_David Manners Group with Alts

I think they are both supplying the Bilsteins

 

The Arnott Remanufactured Front Strut re-uses a stock OE shock and adds the new Arnott Air Bladder as well as new seals and air valve to it. We do test them extensively (as well as clean, recondition and paint them) but they are used.


The new Arnott design does include a new specially-tuned and valved shock as well as the new Air Bladder but does not use CATs. Customers report the ride is between Sport and Comfort. We offer a 30-day return policy of but that does not cover installation or shipping the part back to Arnott's new EU office.


We are also pleased to announce that as of Jan 1, 2015 we now offer Arnott's Limited Lifetime Warranty to customers in the EU as well as North America.


https://www.arnotteurope.com/jaguar-...-products.aspx

 

Basically, the shock absorber lasts a lot longer than the air spring diaphragm, so, Arnott are doing us all a big favour by extending the life of these things. Essentially they are doing to the air springs what one does when a coil spring breaks - replace the spring. You wouldn't throw away the perfectly good shock absorber as well, would you ? Of course nothing lasts forever, but only when the shock leaks or fails to provide damping is the air spring unit ready for the scrapheap.

I have to say I am not a big fan of the CATS, it is needless complication, but if one replaces the Bilsteins with the Arnott units which have no CATS I would think it needs to be in axle pairs at least, and maybe all four.

 

Hi guys, a bit of a follow up.

As you suggested, I replaced the compressor piston ring.
I replaced the loewr control arms (rear), because we found that one of the edge "bushings" (I kno2 it's not a bushing, but I don't know the word for it) is not in the best shape. So we have replaced them, and also the bushings in the lower part of the rear shocks.
The koncking noise on road bumps is still there, and now I got my first C2303 also
I will check the hoses, but I think we reattached everything correctly, so I don't think that there is a tube leak... I don't know whether the re-ringed compressor causes the problem (maybe it can producre higher pressure, which creates more leaks in one of my struts), or what is happening, but I really want to solve this permanently...

Now I think my only chance is to replace the shocks. I'm hesitating between Arnott reman and brand new bilsteins... I slightly like the Bilsteins better, my only problem is, that they do not differentiate between sport and comfort, they give the same part number for both...

 

Ok.... Are you sure you installed the replacement ring the correct way? (Let me tell you I'm highly DIY, studied up and installed the ring backwards!)

Second - did you start the air line fitting at the compressor by hand and tighten to 5Nm? (Again, don't laugh - on my first attempt I stripped the threads in the compressor housing)

What I'm trying to say is double check your work and if you haven't done so already go to each strut, the air block in the trunk and even the air line fitting at the compressor and spray the soapy solution. To see if you can find any leaks.

Just be careful and don't over-tighten the fittings if you find a leak. It will surely make the leak worse.

The only solution (I found) is if you find a leak is to install a new air line nut/olive and trim the air line 3 - 5mm with special air tubing cutters to ensure a clean area for the olive to "grip" the air line.

Or carefully use a utility blade, steady hands and a 2X4 piece of wood and cut straight down...

 

Hi guys, here is the final follow-up

So, after replacing the control arm, as I told, the knocking noise remained, and I called Arnott, because the remanufactured sport shocks were gone from their website. The could find a set for me in a warehouse, so I ordered the full set. I installed them, and... the result was much worse knocking then it was before. Unfortunately the remanufacturing only affects the air unit, and the shock part of the unit I received was in much worse condition than my original one. So I replaced them back, and sent back the reman units to Arnott, I'm waiting for the refund now. LEt me say they are very cooperative so far, and I'm pretty sorry for them because of this whole thing, I really wanted to make this work. Long story short, I ordered the OEM Bilsteins, installed them, and the car is flying on a cloud now Fantastic feeling to drive, without any single noise... The source for the bilsteins was x1-autoteile.de, for the europeans here it's a must have information
Besides, I opted to replace my compressor also, because I think my overhauling was not successful. So basically wverything was replaced, and the car is now perfect. Thanks for all the support guys, Everybody

 

I think it should be noted that OEM Bilstein air spring units cost a whole lot more money; but less than Jaguar sell them at.

 

Sure, though I got a very good price, but it's a more expensive solution .