hello everybody,

I'm a bit confused, for a while now I drive an 03 X350 and i notice everytime i'm driving that there must be something wrong with the way the air-suspension works.

I feel everything, when i'm going over a speed-bump the rear of the car rises up and comes with a huge klunk om the rubber (end) blocks, this i also for the front suspension, and it sways a couple of times .. but shouldn't this car drive as on clouds!

But even worse. e.g. when i'm driving 50 on the highway and there are little bumps in the road, it seems that the suspension can't keep up. It feels that one wheel is coming off the road, the whole front of the car judders a bit to the right and the left and then the wheel comes down again.

Previous jags did ride fine and this kind of behaviour doesn't give me much confidence. Dealer drove the car and said that he noticed nothing....

Am i the only one who determines this, It can't be between my ears because in my opinion the handling when your driving 40+ is even dangerous.

Anybody ant ideas??

 

Sounds like summats deffo wrong - there should be NO klunks!
The air suspension does feel different to any other car I've driven, but it handles superbly well, I do feel the bumps a little, but waaaaay better than other cars on the same road.
I reckon your shock absorber bushes or wishbone bushes are worn out, I'd check that first, any fault with the air system would be giving you messages in the message centre.

 

DJdex, thanks for the quick reply. But can they be worn out after 60.000 mls?

 

My first thought would say no, but I just had to replace both my lower rear wishbones at 70K miles.

 

I would say you have an issue with the air suspension since you are experiencing it on all 4 wheels. Have the system pressure tested.

 

thanks hlgeorge for the reply, but the next question is, how can the system pressure be related to the problem. I always thought the compressor put (what is it) 14,4 psi into the barrel in the trunk until it's full and then when you drive te barrel distributes that pressured air to the shocks. Or is there another pressure going into the shocks?

 

You've pretty much got the idea, but I think you're gonna have to get pro advice, there are so many possibilities - we are just guessing at possible issues, it can get expensive real quick if you just go about replacing parts, a proper diagnosis can be well worth the outlay, once you know the fault, we can work out the cheapest way to fix it. I'd still have all the bushes tested first, they're the cheapest things to fix.

 

If a sensor has failed, those air bags may be deflated or very minimally deflated which is what it sounds like to me. Air suspension may be fine, but a sensor may be letting them stay underinflated!!

 

I had a squeaking and soft clonking noise coming from the front suspension for a few months. I just had 2 wishbones, 2 links and 2 bushes changed and it really changed the ride of the car. It now glides over bumps, but it wasn't cheap at about USD$1.5K for the 6 items and workmanship. The car only has 70+k km on it (40+k miles) but our weather here is famous fro destroying rubber bushes and seals.

 

Wow, it must be brutal to kill 'em in 40K miles! Might be worth your time sourcing some poly bushes!

 

Yeah but I hear that poly bushes increase transmitted vibration and noise so the car may not be so Jaguar like after that... ...although the handling would probably improve somewhat.

 

You're right on that, and I just don't know anyone whose used poly bushes to say how they affected ride quality, be nice to know tho'.

 

I don't know why on earth people put poly bushings on luxury cars. From what I hear, they can be even noisier, AND they transmit more of the bumps and vibrations from the road.

 

I, too, have 40k miles. I experience the same thing you do with the speed bumps, and there is a little bit of scuttle **** in the front end over bumpy roads. I'm pretty sure this is normal for the X350.

 

I am looking at bushing replacement at 77K. It's the labor that's a killer on this one; not the parts.

 

What's interesting to me is how they managed to make sure an enormous car weigh so little. I wouldn't expect such a light car to float like a cloud as it has less mass to help dampen things out!

 

Mine rides very comfortably at any speed. I do notice the suspension tighten up with the sport switch engaged.

 

Really? I thought the sport mode was only for the shift logic! Learn something new every day!

 

AFAIK it is, the sport switch does not have any input to the suspension. The suspension does tighten if you're driving enthusiastically, but that's how it reacts regardless of the sport switch. It also lowers the car when you go above 100mph.

 

That's what I thought. It is kinda cool how it tightens up though when you throw it around. Definitely there is very little body roll on the XJ in any case.