www.jec.org.uk

I have had a Jaguar on the drive since 1999 including 3 S Type R Models and I still have a low miles 2002. I have always admired the X350 and recently bought a 2003 XJR with 82k miles to keep my STR company.
This is my first experience of air suspension and have little knowledge. The car drives well except for what appears to be a lack of damping on the front suspension. If it was a traditional spring/shocker setup I would have no doubt that the shockers were shot.
I have no fault messages and the car is level.
My very basic question is: Is there a traditional shocker inside the unit that can wear/fail like a traditional hydraulic shock??
I am sure someone will enlighten me on this very simple question!!

I've just had a similar problem with my SE - see 'Air Suspension Replacement' thread, in which I received some excellent advice. To summarise, in factory form the system uses a combined spring and shock and it's not practically divisible. There is a US company, Arnott, which makes a conversion kit to traditional coil springs and shocks, but the consensus was that this would risk compromising the ride/handling of any of the X350 models for which it was designed.

It turned out that one of the front airsprings was leaking but this gave the apparent symptom (on my car, at least) of both sides having lost damping. The bad news is that air springs aren't cheap - the best price seems to be aftermarket Bilsteins from SNG Barratt - but the good news is that, unlike conventional springs and dampers, there's no need to replace them in pairs. Before going down that road, however, check the fault doesn't lie with the feed to the air springs - I believe there's a central displacement valve?

Thanks. Very useful info. It's going into AWJ (Stoke on Trent) on Monday to have the a/c fixed so I will ask them to have a look. I want to keep the car standard but the price of units is crazy!!

Bilstein now offer on the alternative parts after market exactly the same units that they supply to Jaguar as O/E equipment and to Jaguar Main dealers as spares. The only difference is that the Jaguar parts are painted in common Jaguar colour paint, but direct Bilstein parts have their snazzy colours applied. They are one and the same units but with an advantageous price difference.

Go to the Bilstein site for details and scroll to the air suspension products.

I no longer buy Bilstein products in the UK, preferring to buy direct from Germany in Euro currency rather than GBP. By doing so you can save up to one third or thereabouts on Bilstein replacement parts costs.

Go to Rexbo.de for the best deals to be had internationally. Suggest you chose the fast delivery service over standard speed. Standard can take anything up to ten days to arrive. It comes fast from Germany, then sits for a few days in Customs before being handed to Parcel Farce for UK delivery......then the brakes go on!

Mike

Thanks for the info Mike. I will go to the German site if AWJ condemn the units. Steve.

Two things.
As far as I know there is no actual steel spring inside the suspension units , i think the air bags provide both functions.
Met a guy at the Western day who had a faulty front suspension unit. He was told by the Jaguar garage that the central fault reporting computer system on the 350 cannot interrogate them to check for faults, it was a question of fitting to see if it sorted the problem. He first went down the route of chasing air pump faults( common) air leaks and manifold problems ( under the boot floor I think) but got nowhere and ended up having to get a new suspension unit, which solved the problem. Does not help you much but useful back ground info I hope?
Let us know when or if you get the problem solved.

There is a cut away diagram of the construction of the air damper units on the Bilstein site. A form of piston damper tube does in fact exist with the so called air bags enclosing the gubbins towards the top of the unit.

Mike k

Update. The offside front suspension unit has been condemned so next job is to sort a replacement. Thanks all for help and advice. Steve.