X350/8 Air suspension unit replacement option.

[J44EAG]

The problem has not yet affected my car but no doubt it will in future years.

In the meantime, here are some air suspension details and some of the options that are now available.

The air springs are prone to leakage given age, mileage and local driving conditions. Cold weather seems to exacerbate leaking issues. You may notice your car squatting on one or more corners which is indicative of a failed air bag on the affected units or an air leak elsewhere on the suspension system. The car may rise when you start up the the air compressor activates. It is mounted below the N/S front dip beam unit. It may be possible to hear that compressor running. Given that the car has risen to the correct height, the pump should switch off. If it does not, then you might assume that you have a leaking air bag on one or more suspension air springs or an air pipe leak. Running the compressor for extended periods, does it no good at all. The compressor piston ring wears out and you are faced with having to fit a new compressor or overhaul with a repair kit. Repair kits are not available from Jaguar but there are several on ebay which includes a kit made by "Bagpipingandy"....Andy Fulton from Scotland. The cost is around £25 delivered. Go back to the X350 suspension system index and look for my post on the matter.

Be aware then that a worn out compressor ring implies there could be another issue with the suspension. Just replacing the compressor or ring is unlikely to be the end of the problem.

(Late edit) Here is how to fit a compressor repair ring kit together with an air dryer service kit. The cost for both kits is around £45 which if successful will save around £215 by not having to buy a complete new compressor. Note however, that you will probably have to drill out one or both of the two head bolts if they snap on you. Mild steel and unprotected aluminium is bad news. Once corrosion has cleaned up, broken bolts drilled out and re-tapped and then all parts smeared with Duralac anti-corrosion paste, rebuild is straight forward.I found the compressor ring on my car to be rather worn at 86k miles. I suggest this work be done again on a repeated 85K basis.https://jec.org.uk/forums/viewtopic.php?f=290&t=11144

Air pipe leaks are usually found where they connect to the top of the damper mounting points. These are easily seen at the front of the car with the bonnet open. If air is escaping, you may well hear a hissing sound. Soapy water applied to the connections might also give away the leak. That is the first check point.

The second point is to jack and block the car with each wheel off the ground. This can be one one at a time. With the suspension extended and with the engine and pump running, you might hear air escaping from the air spring unit. If that is the case, then either a new or refurbished air suspension unit is needed. Look on ebay to see prices of units listed. Prices are massive. Anything up to and above £1000 per unit! Jaguar OE is expensive with Bilstein prices a little lower. You could buy direct from Bilstein as they make the OE units for Jaguar!

You may also come across the Arnott or Strutmaster replacements. These are American companies offering either replacement air units or coil over conversion kits. You will have to find the best deals for these units, do currency conversions, add ex USA taxes, P&P from the States to Heathrow, then pay carriage in the UK to UPS, TNT, DHL, Royal Mail etc for delivery, not to mention about 10% import duty. For a full set of new air springs, you could be looking at a £2K invoice!

I`ve recently come across a UK company, Air Dominance, who operate from Cheam in Surrey. Their workshop is in Chessington. They advertise on ebay and their components are ordered on a direct exchange basis. Today, I made contact with them and had a very useful and productive chat with their salesman, Vince. Prices for a front damper, fully refurbished which includes new internal parts and NOT just the leaky air bag component, are available for a more realistic £359 retail. The product comes with a TWO year warranty with no mileage limitation. The best bit is that during my discussion, I asked about a discount for JEC members. Without prompting, Vince said that as a result of my phone call, he would give 10% discount on one airbag unit and 15% on two units provided members could assure him that they were JEC members. I suggested that he should be aware that members are distinguished by having a five numeric membership number and that if they called to order new units, they mention my name. Only members of the JEC would know my name so the endorsement of bona fidi membership is quite well secured. So if you ever need new airbag units, this contact might save you a little money.

Here is the ebay link.http://www.ebay.co.uk/itm/Original-Jagu ... 2034967773

I`ve begun writing an air suspension article for Nigel. This will appear in the X350 pages in due course.

Mike K

[BrianG]

Top marks Mike! It's good to know there are alternatives available.

[J44EAG]

Yes, Brian. I think this is a very good find for those with high mileage cars that may have ailing suspension spring units.

Those cars may not be worth huge sums but have many years of service left in them. It would be a great shame to see them off the road just because the air units are so highly priced at Jaguar OE replacement level. That fact alone could render otherwise decent cars to the scrap yard. What is particularly good is the confidence and helpfulness of Vince at Air Dominance. As Granny used to tell me, "Its not what you know but whom"!

So stick the contact in your book just in case you need it. These JEC Forum sections are now accumulating a load of useful people and services. Perhaps I can encourage those here to divulge their top contacts, especially where of a specialist nature. It all helps us.

Mike K

[J44EAG]

A heads up note for X350 owners as regards my air suspension article. This is due to appear in the May 2017 edition of our magazine.

This article should be a "must read" for all 350 owners. It aims to clear much of the fog surrounding the suspension system and offers options and suppliers of components, not to mention a blow by blow account of overhauling a compressor.

Those owners with cars approaching a mileage of around 85k would be well advised to consider having their compressor overhauled before any failure occurs. Overhauling before failure will preserve the condition of what is probably an unworn cylinder head bore. This makes fitting a new ring a very cheap and feasible alternative solution to that of having to obtain a new cylinder head or complete new compressor due to finding a trashed cylinder bore. The article also details where to obtain reconditioned suspension air spring units at a fraction of the price of buying new.

The article content brings all my own findings and research together in one place as well as drawing from other internet and manufacturers sites. Nothing like it has ever been written before which summarises everything together in one complete article. My hope is that it will provide a valuable reference for those with an X350 and that it will save them a goodly sum of money if they find themselves with defective suspension.

Mike

[XJSDave]

Hi Mike, Just joined the club after stumbling across your post on X350R tuning. You certainly have a grip on these cars and I was relived to read your comments on air suspension with info about a re-con supplier Cheam. I was looking at a company, Aerosus but much prefer your discovery of Air Dom as original equipment is maintained. I'm quite local to you, Rochester and recently hit an unmarked traffic island in the old kent road (opp Babies are us) which caused the front offside suspension to drop overnight although it seems to have corrected itself now. The car, 2007 XJR Portfolio, never did handle as well as my old 2001 X300. Any slight patches on the road surface would have the front suspension rumbling which on the old system would point to shock absorbers given up the ghost. With the keen price at Air Dominance, I'm happy to change the front air struts just to discover if this makes the car behave as you would expect. I hope to do this in the new year. Just out of curiosity if you know, what happens to the car electronics and monitoring system if the car is converted to good old spring and damper conversion. I have read on various websites about owners who have gone down this road to avoid many other potential problems that may occur with the air system.
Regards David

[J44EAG]

Hello David,

Welcome to the JEC. It is a good place to be. I`ve been a member now for around thirteen years and have to say that without the resources of Club, I would have struggled with maintaining both the S-type V8 which I formerly owned and my current XJR. Its not just the knowledge, seminars or members, it has been contacts gained within the maintenance industry that have significantly eased the journey. This web site facility has also been of significant value. The guys here tend to be DIY orientated which means most are able to input material which is otherwise difficult to source.

As regards air to conventional damping conversion kits, Arnott are probably the best known. The conversion kit agents in the UK are as far as I know, solely Euro Car Parts. At least the name is mainstream and Depots are plentiful. With such a conversion which is obviously less sophisticated, there comes a potential issue with the control module located behind the back seat, Access is from behind the rear seat back. If considering doing a conversion, then one needs to ensure that a bridge out lead or some form of black box comes as part of the kit. I believe this aspect of converting can be the big issue which can be irksome if the correct unit is not sourced at the same time as the buying. It may also be VIN identifier critical. The X350 revision from the early cars went from G49700 to the last of the X358 models. Any thoughts on conversion should have this potential boggy place right on the top of your "questions to be asked" list. Note as well that the Arnott units may also be just basic damper units which may not link to the CATS system so the question has to be asked as to whether you would still have the benefit of an active computer controlled hard/soft system. There is a fair bit about these conversions on Youtube with most of those vids coming from guys in the States where the conversions appear well received. For some reason, the air spring units do not appear to last so long there. The heat appears to have quite an impact on longevity.

Provided you didn`t do significant damage when you hit that island, it is possible that the air-spring has survived with the shock simply causing a blow back through the valve block fitted to the air tank in the boot. Given a short time it should be possible for the air compressor and valve block to have re-pressurised the system and restored the equilibrium.

The system always tries to level the car which can cause some curious visual happenings. Every twenty four hours if the car has not been used and you are standing alongside at the time, you will be treated to the sight of the car "shuffling" on the air-springs resulting in the car rising and falling as it sorts itself out! One effect I witnessed when parked at Canterbury Cricket Ground where I grabbed the only parking space available, was after I parked nose first onto raised ground sited at kerb stone level. So the front was on that high ground with the rear parked down on the road. As I left my daughters wedding reception, the car although floor pan level, had front springs deflated to probably the lowest level possible, with the back end jacket right up! The view was bonkers mad!! Starting up the car raised the front end as I gently reversed back and the front wheels moved off the raised kerb and down onto the level road. As I buckled up and settled in, the car performed a "shuffle" for a few seconds and got back to normal!!

We must hook up sometime. When not at Caterham looking after my parents, I spend at bit of time out on the marshes north of Faversham. A bit cold for that at the moment though. Fellow member Paul (PTJS1 on this site) and I greatly favour meet ups at The Shipwrights Arms at Oare Creek. This is a splendid, original unmolested pub with great food and stonking Kentish real ale. We love that pub to bits. Seriously cosy with oak log fires in several snugs, this watering hole is unbeatable. It is so "un-corporised" you just want to bottle the atmosphere and ambience and take it home with you. Once we are into better weather perhaps in the new year, we must get a gang of us together there for a meet up one lunchtime.

All the best,

Mike

[XJSDave]

Hi Mike, Many thanks for sharing your considerable knowledge on Jaguar cars on various topics. I have been a Jag man from the early days, way back when I bought a 1966 type S with a piston holed for little money, I think I paid £60.00 for it off a friend. I repaired this myself being in my early twenties, since then I have owned two XJ6 a couple of XJC's a V12 XJS, XJ8 308 and currently a beautiful XJR I purchased in April with 37K on the clock. Other cars sprinkled in-between have been Lotus cortina, TR6, Rover 3.5 Coupe, I think my credentials as a petrol head are well founded. I have to say that my present Jag has not been as loyal as I would have hoped. 30 miles down the road, after purchase the MIL sparked up, bought a code reader P4020, tried Terraclean which improved mpg by 4-5 miles, new plugs, new after cat sensor but alas trying to avoid the cost of a replacement unit only added to it. Eventually, Guy Salmon fitted the new cat which solved the problem. Just got the car back from GS again after repair to parking sensors. I love this car and want to get it right, looking at the suspension this morning the offending corner was down again OSF but don't have the funds right now to grace Air Dominance with hard earn cash. It was really helpful to hear of this company and I will indeed replace the two front struts via them in the new year. Looks like a fairly simple job i'll tackle myself. Good idea to meet up some time at the pub you suggested and meet some like minded people, you could have a listen to my engine, I think the water pump is on its way home.....will it never end...ha..ha...Kind Regards.....Dave

[J44EAG]

P0420, 430 and 429 are quite common as pointers to converter or more likely Lambda sensor issues, Dave. (If you have sports 200 cell cats fitted, irritability of the cats and sensors becomes more critical with sometimes high CO output often being noted at MOT time.) Had a 430 myself recently. Replaced NSR sensor and now much more reliable. The image below shows that duff sensor just failing and the trace line plummeting. The left hand image is for the near side rear sensor (duff) with the right hand image for the ok off side rear sensor.

Dropping the front air springs may not be as easy as you think. At the top, the four nuts, the air pipe disconnect and the CATS slug in the top of the piston rod is easy enough. Its when you try to get the T60 bolt out of the bottom fork end that the issues can start.

Note one side of the air spring fork has a captive nut on it. The fork sits either side of the lower drop arm with integral damper bush built into it. A T60 bolt then passes through the plain side of the spring fork, through the integral bush and enters the captive nut welded to the bottom of the other fork.That lot seizes together!

The big issue is that Jaguar never applied any waterproof grease to the plain portion (unthreaded) of the bolt. Given a few years on salty roads, the bolt seizes solid in the bush. What happens when you turn the T60 bolt to unscrew it from the captive nut is this. As you try to remove the bolt, it forces the fork end with the captive nut away from the drop arm, bending the fork slightly. You then find the bolt is still solid in the bush and no amount of WD40 will allow the bolt to be removed from the bush. At that point you wish you had never started the job!

What you then have to do is put a 10mm flat end punch through the captive nut and attempt to bash the bolt out with the punch and heavy block hammer. In worst cases a gas blow lamp might have to be used. You will need to buy two new T60 bolts before you start the job. Originals will probably be at the end of life once they have been extracted. Quite frankly, this is a pig of a job! Use copper grease or Duralac when fitting new bolts.....you might also change the drop arm damper bushes as well. A bench press will be needed for that....

Here is the drop arm with integral, replaceable bush towards the outer end of the arm. It is the larger of the two shown in that location. Now you will see why a press is required for extraction.

Here is a general arrangement image for that front suspension.

The spending will never stop. That goes with running a high performance car. Maintenance is all and we just have to try to keep on top of it. Otherwise we all spoddle off to the nearest new car dealer and buy a new car every three years!

Hope that helps.

Mike

[ptjs1]

Hi Dave,

As you've probably realised, Mike knows more about the suspension setup on x350s than the rest of us put together!

IMHO, I wouldn't jump into changing the air system for conventional springs. One of the real qualities of the 350 is the ride and handling that is afforded by the air setup. I would definitely try and stick with it if you can. I also wouldn't just change the struts because you've got a car that drops occasionally. It could be a loose pipe connection, or height sensor calibration etc. I'm a great believer in not changing any parts unless I definitely know they are the cause of the problem. I think it's worth you doing some really structured diagnosis before you change anything.

I'm sure we'll hook up with Mike in the New Year. I'm just down at West Malling.

Cheers

Paul

[J44EAG]

We will certainly have a Kent Marshlands JEC hook up session once the weather is nice and hot again. The Shiprights Arms could do us quite nicely as Paul and I have already discovered! Anyone else within easy reach of the Faversham area of Kent want to join us for beer and sausages? Call or mail me if interested.

I agree with Paul about the air spring set up. Problems are usually quite solvable. My car used to drop slightly over night. Overhauling the compressor with a new piston ring and new media seems to have cured that slight issue.

Mike

[XJSDave]

Hi Mike/Paul, Very good advice, will look into the air problem in the new year when we have shared a pint. This link should take you to a site where my car was featured not long before I became the owner. https://www.flickr.com/photos/139439575 ... 5833245693
Look forward to our meet up, could even make it sooner, would have to be a weekend or evening. Regards Dave.

[J44EAG]

What a stonker of a car, Dave! I just wish I could keep mine in that condition. At the moment it looks like a JCB that has been in a mud fight! The snowy weather doesn`t help or does my huge dislike of hoovering my car out. (Sciatica 1, Mike 0). Regular daily trips through the back lanes to East Surrey Hospital to visit my Father really don`t help the appearance of the car.

I`m presently holed up at my parents home in Warlingham due to my Fathers predicament and having to keep an eye on my Mother. I can`t see myself back up at Faversham until around the New Year at the earliest, so any meet before then at that location isn`t really feasible for me. However, I`m currently at Warlingham near Caterham in Surrey just off the A22 and have a fair amount of time on my hands. Anyone who fancies a pie and a pint and is in the area is welcome to give me a shout and arrange a suitable time and place for a noggin. I`d welcome the break from the present routine!! My contact details on the X350 pages in our magazine.

Mike

[3.8etypephil]

Dave, that looks a very nice car. Black 350/358 XJR = the dog's, as I'm sure Mike will agree.
I'll join you lot for a beer in the new year; I grew up in your neck of the woods and have offspring over your way whom I could visit on the same trip.

[J44EAG]

This meet up idea seems to be gathering momentum. I eventually envisage something a bit like the Kemble or Coventry breakfast type set ups. Anyone else like the idea of something based around the Sittingbourne, Faversham, Whitstable area? Let me know. I`ll open a new thread on this subject shortly. Lets all stay in touch on the idea.

Mike

[XJSDave]

Hi All, Glad the car meets approval, I did pay double dear, I had looked at several just window shopping but when I came across this one I nearly couldn't hold my water 37k miles, right colour, wasn't sure about the aluminium interior but now quite happy with it,begged and borrowed to buy the sweetie so you can see why I want to get her tip top as she should be. I'm really chuffed to meet like minded people who know their onions and look forward to events to come....Regards..Dave