I've spent a few hours searching the forum for posts on whether the shocks on the 2004 XJ8 can be replaced with aftermarket shocks and can't seem to find a definitive answer. I see a bunch of "do a search on the forums" comments, but can't seem to find the original posts.

Is there a stickied post somewhere that shows what the aftermarket options are for shock replacement?

I believe I have a bad front left shock after spending $120 to have a mechanic put the car up on the rack and look around. Medium to large bumps make the front left wheel feel like it is bouncing around and there is a clunking/wobbling sound from just past the dashboard, and a fairly intense impact sensation. At first we thought it might just be a bushing but there is a film on the front left shock in comparison to no film on the front right and the wheel's wobbling effect indicates to the mechanic that it is the shock.

I'm hoping I can find an aftermarket replacement of the airshock for less than the $1200 part price quoted by the mechanic.

Thanks for the help!

 

They last a long time , but are expensive to replace. Do it once do it right and be set for another 100K!
Option B is find a junkyard/partshop with a Jag on hand to strip out the shocks!!

 

Cali,

At present only 1 supplier of rebuilt air shocks is out there. ARNOTT INDUSTRIES @ 1/800/251-8993. Google them to find their web site.

Dude. You need to tune up your search skills on this forum as references to Arnotte abound. You did not mention any issues with ride height dropping. That is the typical failure mode with a leaking air shock. Good luck!

 

Thanks, Tarhealcracker and ddsski. Looks like I'll go with the Arnott. It would be nice if there were a sticky poll of satisfaction with the shocks after six months or a year, etc.

Also, I'm not having a ride height problem other than the entire front end seeming a bit high. Occasionally I'll see a ride height adjustment at a stoplight but I've assumed it's been related to the pavement angle.

What I am experiencing is a small clunk over medium sized bumps that sounds like it's coming from the drivers dash and then a bit of a wobble in the front left wheel.

On larger bumps it's a very intense impact and the wheel really feels like it is wobbling. There's also a film on the shock that the front right shock does not have. Also, the air compressor and a relay were replaced in June by the previous owner but I can't get any further information as to why. No shocks were replaced at that time.

If anyone has any additional thoughts I'd appreciate them. Thanks!

 

The design unfortunately uses a combined air spring/shock assembly so the shock absorbers cannot be replace separately. Would that one could do it !!

As posted, the only after-market supplier seems to be Arnott Industries. These units are very similar to those on the Range Rovers. Some people have managed to change to steel spring units so they can ditch the air spring system which can play up so much.

 

Thanks for all of the input. I replaced the front left shock with an Arnott and it fixed the issue of the wobbling and noise.

I'm still having an issue with how rough the suspension feels on larger bumps. It seems much rougher on the bumps than I would imagine a Jaguar to feel (I'm a new owner, the 2004 XJ8 has 54k miles). The mechanic believes that the suspension is now working fine and that the Continental Contipros are to blame. He thinks the current tires are terrible and are not only transmitting the impact of bumps but the noise of the impact as well all in addition to noticeable road roar. A tirerack salesperson seemed to agree that the stiff sidewall of the Contis are to blame. They suggested the Dunlop Turanza Serenity tires would be much softer and quieter.

In trying to find a place to install the tires, a local tireshop offered to check the existing tires. They claimed that the 2004 XJ8 has a stiff ride and that it's not the tires but the design of the suspension. I find this hard to believe, is it true that the comfort suspension is made to be sporty and to transmit the bumps and noise of the road or do I really just need to change the tires?

In case it matters, the fronts look like they have 5-10k of wear and the rears look like they're about at the end of their useful life.

I'm really sensitive to road noise and bought this car because I thought it was one of the quieter vehicles around.

 

Well just a couple of thoughts:

1. I don't think of the XJ as having a rough ride or being unable to absorb bumps. Certainly, compared to old time Caddies it's rough but not by modern standards. Was it rough before you had the shock replaced?

2. I find it hard to believe that your tire brand could account for a rough ride. You do have standard sized wheels and tires don't you?

3. What about the ride height of the car? Is it normal and not setting unusually high? If the air suspension Gods get confused the shocks will be hyper inflated, raise the ride height all around and give you a very rough ride and no capacity to absorbe bumps. But you should get an error code if this be the case.

4. Installation of an air shock by one who does not know the rules can result in a confused air ride computer, destroyed height sensor, etc. ect. Your mechanic was Jag qualified, right?

Now Cali, there are several important questions above. This is important! Answer each and all and I bet we can zero in on your problem.

 

Very helpful, thanks Tarheal!

The ride was much more rough before the shock was replaced.

The wheels are standard sized but I just realized there are three Continental eco tires on the vehicle, all relatively worn and one new Contipro tire on the front right. I felt like an idiot when I realized this, but at least it's another reason why the ride is rougher than expected.

It was mentioned by the mechanic that the front end seems a bit high. No warning indicators on the computer or on the dash, not sure if it's an illusion.

The mechanic is Jag certified.

At this point I'm really thinking its the different tires on the front left and right of the car. As well as the uneven age between the two of them and the comments on an S-type tire thread that the conti ecos are:

"I had Conti EcoPlus Tourings on it and found them to be among the crappiest tires i ever had on a car. I couldn't wait to get them off as the car vibrated at low speeds (tire defect)."

Kind of an embarrassing post to make, but such is life. I'll rectify the tire issue and post on the results.

Thanks again, Tarheal.

 

Okay Cali, Here's the deal in order of importance. Keep in mind I'm not a pro at this, just an experienced amateur and you just add IMO before all my points:

1.Your car air ride computer is confused and has hyper inflated the front shocks, and probably the rears as well, as evidenced by the elevated front suspension.
This accounts for the hard ride. Not the wheels or tires. You will have to get the car to a dealer or service provider who can run the ride computer softwhere.
You might try disconnecting the batt. positive lead and grounding it before reconnecting it. You do have yoiur radio code don't you? Sometimes the air ride system sorts itself out this way.

2. Your mechanic is not up to the job. If he had observed correct procedure the air suspension would not have hyper inflated, he would have recognised the problem and he would have known the emplications of an elevated suspension. And he would not have fed you this BS about tires causing your hard ride.

Keep us posted. We want to stay with you on this.

 

Thanks again, Tarheal. I greatly appreciate your time and advice. I'll look into the suggestions you recommended and post the results. Best regards!

 

I have a 2004 Jaguar xj8 that is driving me crazy with this "Air Suspension Fault" message that keeps coming up.
My right front seemed to be about an inch lower than the rest of the car so the jaguar mechanic ran the usual test and came back with a code saying I had a leak. So I replaced the right front shock. Still got the ASF message. Now have replaced the module, and the relay, and still am getting the ASF message. Now they are saying for me to replace the air compressor, as that may be the problem. Why can't a Jaguar mechanic with the computer program find the exact cause. Is the system that complicated.
Does anyone have a good idea before I put on the new air compressor, that may or may not be the solution.

 

Formworks'

Can you confirm that your Jag Tech is qualified and working at a Jag dealer with the approved Jag software. There are 3 types of software, as I understand it, the type that diognoses the problem, the kind that equalizes the ride height and the suspension and set up program for the computer/module. Maybe one of our more informed contributors can chime in on this.

There are a few indi shops about that have made the software investment, AllJags in Orlando being one, and of course the dealers. After replacement of the air shock or the module one or more of these programs needs to be installed.

All that being said, it is not unusuall for the air compressor to be trashed by a leaking air shock that was ignored for too long. Replacement of the associated relay is allways a good move. Like you, however, I'm a little uncomfortable that your tech seems to be hip shooting.

What say you Brutal or Stevetech?

 

Tar heal you wrote:

All that being said, it is not unusuall for the air compressor to be trashed by a leaking air shock that was ignored for too long. Replacement of the associated relay is allways a good move. Like you, however, I'm a little uncomfortable that your tech seems to be hip shooting.

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I write

Okay, since my next suggested option was to replace the air compressor I am still reluctant to do this because it seems to be working. We deflated the front and the compressor completely inflated it back in exactly two minutes. That makes me think the compressor is okay.
Could it possibly be leaking and perform like that. Or are they two different issues.
I am planning a trip to Kentucky over xmas, about 2500 miles round trip including extra driving. I'm wondering if I can take the chance it will be okay. This "air suspension fault" light has been going off and on since September.

By the way, my last tech was done at Alpine Jaguar, the local Ft. Lauderdale dealer. He wanted to keep the car for a day or so and isolate the problem by watching to see if it goes up or down. He called it something, but I forgot. Somehow, he claims he can determine if any lines are leaking, and where. Why can't his computer program figure that out right away.

 

I was hoping to hear from someone regarding my recent post. I am about to buy an air compressor next. Not sure if this is the answer though.
"Air suspension fault" keeps coming on even after replacing the right shock, the module, and the relay. Only the right side has ever dropped, and that side only about an inch or less. Hardly notice it. Have to put a tape measure to it to tell.
Certified Jaguar mechanic can't figure it out yet. He keeps saying code says it's an ait leak. That's why I have replaced what I have to date.
Light is never on after sitting overnight. Comes on after I start up and go several miles. Sometime only after a few miles, and other times I might go several miles. Up to 200 or 300 plus miles.

Leaving Sunday for the holidays on a 2500 mile driving trip. Wish me luck!

Formworks
Ft. Lauderdale
Jaguar 2004 xj8

 

He keeps saying code says it's an ait leak.

Meant to say AIR leak.

 

8 times out of 10 .. here in canada the air compressors dont do to well..
every time it gets cold.. we replace 10-15 compressors to 1 shock.

 

Differentiating among air spring leaks, line leaks, bad air compressors is not really a guessing game. There are two codes - C2302/C2303 "plausibility Errors" that have a direct causal link with a failing air compressor. The problem is - any C-codes cannot be read by almost any scan tools, thus the guessing game.

We can call it intelligent guessing though, as said, 90% of the time, the air compressor is at fault when an Air Suspension fault shows on the dash. Experience taught us to replace the relay along with the compressor as it always takes quite a beating. In fact, there is an aftermarket relay (direct replacement) that I will NOT use in this position because it fails almost immediately, and the only relay I've found works is an OEM.

As 350s get older and this system begins to suffer age and parts problems, there will be efforts to convert to a traditional strut. In fact, I'm aware of efforts by one commercial enterprise already and I have interests as well.

I'm Stevetech BTW, suffering from a name change.

 

i dont use the "traditional" Jag diag anymore, its too iffy on which springs are leaking. Thats why I made these to test.
https://www.jaguarforums.com/forum/s...ad.php?t=42703
You need to know what bar the reservoir is inflating too and how long to diag the air compressor. I would be concerned about what code theyre reffering to also. only really 2 like
Steve said. leveling plausabilty, (leaking spring normally), and reservoir plausabilty(compressor/relay normally).But Ive also seen issues with a spring replaced and cailbration being out after spring replaced and car learned a different (incorrect) ride height. Its not that common but Ive have a few. you have to reclaibrate the air suspension with dealer software(IDS/SDD/WDS) It doesnt level correctly to its target and gives a suspension fault in the message center

 

Just wanted to update you Tarheal that after changing the tires to Bridgestone Turanza EL42's that the suspension is behaving properly again. The Continental eco plus tires were so rigid that every bump was a jarring experience. With the Bridgestone's the car feels like a Jag should, smooth. Thanks for all your help!

 

CaliJag;

Congrats on the new tires but I don't thing they were your harsh ride causation. Heres what I think happened. Keep in mind this is a WAG. Your air ride suspension computer was confused as a result of the defects and all the work that had been done to diognose and correct the problems. It had placed itself in the hyper extended mode and convenced itself that all was well.

When you placed your car on the rack with the suspension hanging down & fully extended, the system sensed that something was amiss and reset itself to the proper condition when you lowered the car.

Here is how I arrived at this conclusion. Back when I had a temp. sensitive leaking LF shock I took the car north in the Winter and let it set out overnight. When I came out the next morning the car had setteled all the way down in the front. When I started up the car it threw a few codes and rose up at all 4 corners in a hyper extended mode. No amount of fiddeling would get it back to normal. I drove it 500 miles home to a warmer climate and let it set over night. The bad shock leaked somewhat over night, enough to alert the system that it needed to reset and all was well.

Since your shocks had no leaks there was no way to signal the system it needed to reset/recal. so it just stayed hyperextended. Placing the car on the tire rack signaled the car to recal/reset the suspension.

The above is not an educated theory but the result of nursing and repairing a leaking air suspension system for 18 months. I makes sense to me I hope It does to others.