X350/8 Air suspension unit replacement option.

[J44EAG]

They were operating from an office in Cheam, Surrey and a workshop at Chessington, Surrey when I first came across them.

That is all I knew about the company other than to say that several other JEC members subsequently made use of their services and I heard no complaints just compliments. It would be interesting to find out if they are still operating even if under another title.

Mike K

[PaulGover]

In my opinion, the "Air Dominance" web site looks unreliable. The "English" has the strange syntax that suggests the writer was not a native English speaker - not in itself a problem, but you'd expect someone in Cheam (where they claim to be) to have a local to check the spelling and syntax. The link on the home page to the site developers "Sebiat.com" takes you to a Bulgarian web site with rather similar syntax, or actually, rather worse, what looks to be a joke. They appear to be based in Pazardzhik, Bulgaria.

Air Suspension is a real company registered at Companies House, #08870523, with a single (Bulgarian) director Emil Nikolov, based in Hounslow, and a net worth of minus £14,558.00 as of 31st Jan 2018. They had assets of about £6,000, and 3 staff; their corporation tax bill was about £4,000, and their VAT bill about £3,000. There's no details of their turnover, but they appear to be a very small company; they have 100 shares, all owned by Emil as of 31st Jan 2016. From the VAT bill, their turnover might be around £15,000, which is below the registration threshold, so the VAT number you have may be historical and no longer relevant.

("Air Suspension" is not the same company as "UK Air Suspension" (#8943872) of Didcot, nor "AS AIr Suspension" (#06243526) of Warrington, nor "On Air Suspension" of Ongar.)

The Companies House information shows that they moved their office from Air Dominance's address in Cheam to 206 Heath Road, Hounslow, TW3 2NX in February 2017. Google shows that address as a house, so they presumably have a workshop somewhere else. (It's not uncommon for the registered office to have little relation to the actual working premises.) It may be an accommodation address; there seem to be several property management companies, with different directors, registered at that address- also not unusual.

[trampintransit]

sorry to drag this back to the start, but I'm a bit unclear about how to diagnose the order of failure between the struts themselves and the pump? If the pump's running all the time ( How do we tell ?) then that could be 'cos there's a leak ( Which we maybe can't find ) of 'cos the pump is tired. How to we isolate the pressure drop to pump or strut?

[tomi834]

RMT as in Rebuilt Master Tech has these quite cheap, although they come from outside of EU, so there would be an additional 24% cost added to the price shipped (770USD/pair), so it would be about a thousand dollars, which would be about a quarter of what Bilsteins would be here in Finland. They do remanufacture, but I did not see any mention about core deposit. They state that the parts have "limited lifetime warranty", which is not explained anywhere on the site. Anyone tried this?
https://rebuildmastertech.com/jaguar/xj ... uspension/

I contacted them via ebay. They did not answer all of my questions, but it became clear they would be unwilling to sell to Europe, even though I actually could buy them via ebay. Their guarantee was also a bit unclear, but what they did tell me was that it would not cover import- or shipping fees, so the risk is a bit too much for me.

Does anyone know if these are remanufactured anywhere in Europe or in the UK?

[J44EAG]

Other than the Chinese imports on eBay, the only people I found were Air Dominance at Cheam in Surrey. They would now appear to have as far as we are concerned, gone to ground. The current situation remains very unclear and essentially, closes an avenue to us.

Mike K

[cornershop]

Has anyone tried the units from Miessler?

They appear to offer a budget, midrange and the usual Bilstein option

http://www.air-suspension-shop.com/Suspension_15

[J44EAG]

That is most useful. Thanks.

I`d suggest we all bookmark the link for future reference.

All the best.

Mike

[trampintransit]

J44EAG .. you said earlier

" It may also be VIN identifier critical. The X350 revision from the early cars went from G49700 to the last of the X358 models"
with regard to replacing air struts with coilovers. Have you heard of coilover replacements not extinguishing the 'Air Suspension Fault ' light if the supplied 'black box ' isn't coded for this pre/post G49700 point ( I'll need to check my VIN plate..I assume that number is in the VIN number?)

Only the Arnotts coilover kit seems to have black box anyway? And I'm struggling to find a UK distributor for them. I'm REALLY surprised there aren't other manufacturers in Europe / UK offering coilover solutions.

I've seen references to a DIY solution to fooling the system after air strut removal but nothing illustrating an actual solution?

[J44EAG]

The last six alpha/numeric digits in the VIN give your specific car build identifier.

Going to conventional Arnott type coil over dampers will require an electronic bridge unit to be fitted and to fool the car electronics into thinking the air dampers are still present. Which unit is required for a particular car is probably best advised by Arnott. Although I`ve heard of Black Dog replacements, I`ve not seen anything on line in their ads which hints at the bridging unit. As far as I know, only Arnott and Black Dog appear in any internet searches as suppliers for coil over units suitable for the X350.

Our good friend Steve Howard, originally active on the X300 section of this site, recently wrote and article about acquisition of a X350 and his fitting of Arnott conventional dampers. The conversion went well. Steve would certainly be the fellow to chat to about the conversion...in fact he is probably the only member on this site who has such a conversion. Steve`s user name is "Pops Jag" and the best way of contacting him is probably via the private message (pm) facility on this site.

Hope that helps.

Mike

[trampintransit]

Ah..not even heard of Black Dog thus far....quick google reveal an American manufacturer of bicycle suspension...is that them? I shall dig further. .. Cheers for all that.

Edit...I'm clearly not smart enough to use the PM facility....I don't understand how to search for a username, it says I 'don't have the authority or some such thing?

[J44EAG]

Rather than get into technical aspects of the site, I`ve mailed Steve and asked him to drop onto this thread and advise on his conversion. Watch this space.

Mike

[Popsjag]

Hi Gents,

So, if you want to find out about the Arnott conversion, let me begin with a little story ( I did write an article but it's never appeared in the magazine, to date):

As usual my tinkering urges have been getting the better of me so, around July 2018, I had a Powerflow stainless steel exhaust system fitted, from the cats back. The first system that was made sounded very nice, but droned around 50mph, so back it went to be modified. The second system was much better, but still gave it a bit of a V8 growl!
During all these ‘little enhancements’ we were very happy will our initial purchase, but in late September 2018 we were about to be bitten – the air suspension dropped at the rear and wouldn’t rise back up properly. Luckily it happened at my place of work, which was only a ten-minute drive from home. I managed to get home with it half raised and get a jack under the rear of one of the sills before it deflated completely.
The next day, I noticed that the front had dropped slightly as well and when the engine was running the car refused to raise up off its laurels – with the dash displaying (if I remember correctly) ‘levelling plausibility error’. After seeking advice from more knowledgeable people than myself, I decided to start by replacing the rear level sensors (that attach to the rear lower suspension arms). This did not appear to improve the situation and. Unfortunately, I couldn’t take the car for a run to see if the system would inflate to the correct height. This was due to having slightly wider wheels than standard – leaving the rear inner arches sitting on the tyres!
I decided the next decision was whether to replace all four suspension units with second-hand ones (would this cure the problem, or will I have to replace these and more parts in the near future?) or replace them with brand new units?
Alternatively, was there a conversion kit ‘out there’, to replace the whole air suspension with coil-overs (and if so, how much)? To answer that question, I went on numerous internet sites to price up the air units – the prices varied from £400 to £700 per unit! I did the same with regards the coil-overs and came across a company called Arnott, who did a complete kit (including a module to stop any warnings popping up on the dashboard).
After enquiring about agents in the UK (I believe Arnott are an American firm), I found out that Europarts were an agent – very handy for me, I thought, as they have a branch just 8 miles up the road in Chester! So I got on the internet and perused their site to see how much this kit would be - £1,695. Not a bad price I thought, considering I would no longer have to worry about compressors, pipework and air struts ever again. Now if you’ve got experience of buying from Europarts, you always buy through the website and hopefully get a discount code to use – never just call in and pay over the counter! Needless to say, I ‘played’ with a few codes over a couple of weeks, before finally getting the kit for £1,136 – not a bad discount, don’t you think? The only downside was (obviously) that I couldn’t just pop to Chester and pick it up – it had to be ordered in, possibly taking up to 2 weeks. So I paid the pennies and awaited for free delivery to my door.
About 2 weeks on a man in a van delivers a large box for me. I ask him where’s the other box (because I know from my research that it comes in 2 boxes) but he’s adamant that there’s only one – and the large box does state ‘one of one’. So I sign for it and off he goes, whilst I open up said box to investigate just what has arrived. Inside is a load of packaging and another, slightly smaller box. Clearly marked on the outside of this box is ‘Box 2 of 2’ – so where’s box 1 of 2? I open the smaller box (I hasten to add that I have been taking photos of each stage) to find 2 smaller boxes, containing the two front suspension units – so where’s the other two?
Upon this discovery, I phoned up Europarts to explain what I have received and guess what the first question I was asked – have you opened the box? I felt like saying ‘No! I’m that smart I know what parts are missing without opening the box!!’ Putting my sarcasm aside, I was very diplomatic with my reply, informing him that I had taken photos and would forward them to him via email and please could they rectify the situation as soon as possible. After about a week I was informed that they would pick up my box, at their expense, and re-order another complete kit.
About another week later and I was notified that they had found the other missing box and a complete kit will be on its way within the next few days. Needless to say, a parcel duly arrived and upon checking it contained my original box (as it had the heavy tape around it that I’d used to send it back) and the missing second box – now we were back in business!
Obviously, the usual health and safety applies when working under a vehicle so after loosening all the wheel nuts, Slater was jacked up and placed securely on 4 axle stands under the front and rear subframes ready for work to commence. I placed them under the subframes because I would need full movement in the lower wishbones. After removing the rear wheels, the handbrake brake calipers will need to be removed and supported to allow access to the strut bottom securing bolt. Also, the rear link bar (where it attaches to the rear of the hub carrier) will need to be unbolted to allow enough clearance for the strut to be lowered and removed. There are also 4 nuts on the top of each strut and a wiring connection, inside the boot area. This means you have to remove the trim from both sides of the boot to gain access. You also need to remove the air pipe (no longer needed), but do this carefully in case there is any compressed air still within the system – none in my case. Important note – support the lower wishbone, with a trolley jack, BEFORE removing the 4 top nuts! Once the bottom bolt, air pipe, wiring connection (which just pulls out of the top of the strut) and the 4 bolts have been removed, you should be able to safely lower the strut down and out between the lower wishbone and the detached link bar.
To fit the new shiny coil-overs is just a matter of reversing the above process (without the air pipe and wiring connection, which can just be secured tidily out of the way as they are now be redundant). Repeat for the other rear strut and then move to the front ones, (after DOUBLE CHECKING that all nuts/bolts have been tightened fully) where it gets a little bit harder.
Replacing the front air suspension assembly requires the bottom wishbone to be supported with a trolley jack initially. The sway bar (anti-roll bar) lower link must be unbolted from the lower wishbone. Then you will need to remove the four nuts and wiring connection (as per the rear ones) and the bottom securing bolt, which has a torx head. This can be very tight and, if you are unlucky, seized. Fortunately, both of mine were not seized! You will then need to remove the nut on the upper wishbone, that attaches to the hub carrier/ brake disc. This may be stubborn (as I found out) as the ball joint started to rotate on one of mine before I could remove the nut, so I ended up using an angle grinder (as I didn’t have a nut splitter) to cut nearly through the nut (so not to damage the threads). DO NOT attempt this unless you have the confidence to do so, using the correct PPE (goggles, gloves, etc). Once the nut is removed, carefully lower the jack, whilst also supporting the hub carrier. The suspension unit should lower as the bottom wishbone lowers, allowing you to lift it off the wishbone as it becomes free of the upper wheelarch mounting. Ensure that you support the hub carrier so you don’t put undue strain on the lower ball joint. Refitting the new strut assembly is the reverse of this method. Repeat on the other front suspension assembly. Don’t forget to secure the redundant air suspension wiring connections out of harm’s way (and it looks tidier!). DOUBLE CHECK that all nuts/bolts have all been tightened fully!
Then it was just a case of refitting all 4 wheels, removing the axle stands, lowering the car back down to terra firma – not forgetting to tighten all the wheel nuts!
Now before you get too excited and go for a test drive, to admire your handywork, you need to fit a module (supplied with the suspension kit) to the wiring to the jaguar suspension control module. This will stop any warnings appearing on the dash! The jaguar module is neatly hidden behind the rear seat – so you need to remove this to get to it! The bottom seat squab needs to be removed first – there are 2 retaining clips, under the leading edge, with a serrated lever that you should be able to get a finger to and slide sideways (whilst using your free hand to apply some upwards movement. It is tight but can be done. Once the squab is released, it can be pulled out of it’s ‘resting place’ but don’t be too abrupt – there are 4 wiring connectors to the rear of the squab (2 on the right and 2 on the left). If you disconnect these, you can remove the squab from the car, giving you easy access to the seat back. There are 2 cords (1 each side) at the base of the seat back. Pull both of these and the top of the seatback can be pulled forward, giving you access to the module. This is hidden behind the insulation. Disconnect ALL the wiring to the module and connect the new module to the wiring harness, as per the instructions supplied. DO NOT reconnect any of the old harness to the jaguar module. Secure all the wiring and the new module back behind the insulation, then refit everything in reverse order.
Now you can go and enjoy your handiwork!

In the photo with the black module (air suspension), you can see a brown box - this is the gadget that stops you getting any warnings on the dash after the conversion.

If you want to ask me any more questions, please PM me or get hold of me through Mike.

[J44EAG]

Thanks for that, Steve. Very useful.

Perhaps you could describe how the car now drives. Is it an improvement? I`m assuming that the Arnott coil over kit is non CATS. If that is the case, how do you terminate the old CATS plugs that used to connect to the air dampers? Presumably you just tidy them away?

Mike

[ptjs1]

Steve,

Good job!

It's a shame the article hasn't been published. Mike is usually very good at publishing things that have been sent by owners. When did you send it to Mike?

Cheers

Paul

[Popsjag]

The Arnott suspension is NON CATS, so you just tie/conceal the old connections away.

The new suspension is a bit softer (mine being an XJR). The only thing is that the back end obviously can not 'self-level' any more, so you know when you've got a load on it (i.e. when towing or your rear passengers are on the heavier side). I use mine for towing the caravan, so I added 2.5mm spacers between the top of the new 'strut' and the body mounting (made from wheel spacers) - it helps a little,but sits slightly high when empty (but not too noticeable).

In answering Paul's question re the article, I sent it direct to Nigel Thorley. I've also done an article on removing and repairing an XKR supercharger (I know it's a different model) - same result Perhaps Nigel is swimming in other articles?

Regards, Steve.