Hello Everyone!

Well the time came when I had to make a decision. During the winter months (especially when below 35F) I'd wake up to a dropped front suspension. Below 30F it was very difficult to even get the front end to lift due to the slight leaks in the front shock(s).. Summer months no issues.. Then recently my passenger rear shock went to heaven...just happened suddenly. I had to decide..... replace the air shocks (at least three) or do the coil over conversion.. Basically it came down to cost... Replacing 3 to possibly all the air shocks plus maybe a failing compressor (since it's been overworked) or just due the conversion.

My baby is my daily driver (25-30K miles/yr) but pampered and maintained w/165K miles. I absolutely love the ride w/ the air suspension, so it was a hard decision, but it came down to cost... If it was a show car w/ low miles I would have spent the money and kept the stock system, but not worth it for a high mileage daily driver.

I installed the Strutmasters kit today and took it for its first ride. Not bad! but you definitely lose some of the butter smooth ride quality it had with the stock system. You noticed the difference during local driving on roads with imperfections. You just "feel" the bumps more with the coil overs. On a smooth highway drive barely any difference at all.

I'm happy with my decision and would do it again based on the condition of my car. I'll miss the stock system for sure, but I'll get used to this new ride.

Just wanted to share my experience with everyone.

Thanks!

 

I have just ordered my 2nd & when the next one goes, I plan to do what you have done. Thanks for sharing your experience.
Best,

Steve S

 

No problem Steve! Hopefully no more issues with your system

 

My previous X350 had already been converted when I bought it, so my current ride is my first with air suspension. I'm a little over 100K and very cold temps cause my front shocks to go down, so replacements are in my future too. What makes me curious is that my ride isn't "butter smooth" at all. I feel every irregularity in the pavement, especially at slower speeds. Is it possible for the air suspension to age in some way but not collapse?

 

Absolutely it is. My car, when I bought it, would sag overnight, come up within a couple of minutes of starting, but the ride was VERY harsh, almost like my slightly-lowered Miata! I have no idea what a working air suspension feels like because I've never been in one. I also have no idea why my car rode so rough.

All automotive air suspension systems have a couple of serious design flaws: they don't have a separately serviceable dryer, and they have no way to remove water from the system. The desiccant chamber is inside the compressor, so servicing the dryer, i.e. replacing the desiccant beads, requires removing and disassembling the compressor. Along with that flaw, there is NO WAY to remove water once it gets into the system. It will collect in the shock bladders, in the valve body, and in the compressor, and everything it touches will eventually rust. I will never in my life buy another car with air suspension unless it has had these failures addressed. I live in Florida, with very high humidity, and the inability to keep water out of the air system is a fatal flaw. When I unhooked my compressor for initial troubleshooting, water poured out of the air outlet. The dryer chamber was literally a water tank. I ordered a set of Arnott coilovers and never looked back, as getting the air system working, and clear of water, would have meant a complete replacement, which would cost more than I paid for the car, with NO return on value.

With the coilovers, it's the smoothest-riding car I've ever owned, and that includes some 80s American big sedans, like Grand Marquis and Crown Victoria.

 

Great response and explanation on the flaws in the air suspension.

I drove the XJ over 250 miles this weekend and very happy w the conversion.. but I liked the air suspension when running.. on my 04 XJ I did NOT like it .. too soft and car was all over the place on high speed turns.

 

The Air Suspension isn't that great you know (even though I retain it). Possibly because the X350/X358 is designed for the sporty youngies of today.
It Is Not Suitable For The Queen Riding In The Back (or in my case the wife).
My Honda Elysion van has less noticeable harshness. Although that may be due to expectations...:-)
(My wife does actually ride in the back seat of our Honda Elysion, because the passenger door knob is broken. She can ride in the front of the Jag though)

 

Although I'm glad to know., that there's an option to install a conversion kit, it's a ride quality downgrade in my opinion.
I once drove a X350 with Arnott conversion, which felt just like my other cars. On a straight road up to 100km/h, coils and air springs feel the same.
But on german autobahn, above 160km/h, the air ride makes a big difference. The coiled X350 felt unstable and not like "riding on a flying carpet".
On bad roads with lots of bumps coils feld "hard and jumpy", while air springs make a big gain on ride quality.

Driving the X351 was a disappointment on ride quality as the removed the air springs on the front (which I didn't know at testdrive).
But also air springs can provide bad ride quality, when I remember Model X of Tesla.

 

Wfooshe, quite a great explanation - thanks!

11 years ago, I replaced the driver's side front air shock with Arnott &, at the same time, rebuilt the compressor. I didn't notice any water or corrosion. Like most of you, I have owned some of the finest cars built. I have had my x-350 longer than any car I've ever owned; one of the principle reasons is the ride - I can't imagine a nicer one. As I previously mentioned, I have a new shock arriving for the other front today.

Hoping to live long enough to get out of the valley. If I do, I'll report back on how the suspension is with the new shock.

If I don't live long enough, my wife is threatening to have me buried in the car! Sounds like a good idea. Have you known anyone else to do that? This might be some kind of Guinness record thing?

Best,

Steve S.

 

Thanks for posting. I still have the original air in my 06 and will most likely convert it when it starts acting up. Luckily this winter wasn't too cold so she barely sagged in the mornings, even after being left for a few days.

Since yours is an 06 as well, what did you do about the dash lights? Does the Strutmasters kit come with the box to wire into the suspension module? For some reason I thought only the Arnott kit came with that box. I would really like to go with BC coilovers, but I could never live with the lights on the dash and on the 06+ I believe you need the box.

 

I have exactly the same issue I have a 2006 4.2 n/a long wheel base and I can't justify the additional expense into the air system after pumping lots if money into it already having already changed all 4 shocks compressor and valve block im ready to cut my losses and go for the bc racing coilovers. As far as i know you plug a resistor into each plug that would normally connect to the air shock this then fools the system into thinking all is good with the air system that you then no longer have. I'm in the UK not too far from london so i think bc racing coilovers is the best option here.

 

Interesting, do you have any more info on the resistors? I really would like to go with the BC Coilovers, I heard they ride very well and you can set the ride height to wherever you want it. Once thing I'm not crazy about on cars converted with Strutmasters/Arnott is the ride height, never looks quite right to me.

 

I just purchased another Xj wich needs some work first. One thing I am certaily going to do tomorrow is taking of the compressor to change the dessicant beads.
I also had a real Pool in the drying chamber dark brown and black beads on the original compressor on my first xj8
bought a new compressor tried to refurbish the original but it was absolute junk .
Humidety in the system is probably the cause for all the other problems.
once your beads are exchanged I suggest to let the car run so it can raise the airsuspension and fill the tank. Then open the hood and unscrew the brass fitting of the airstrut one by one with a jack under the car so it does not drop below 340mm. Just to release some of humid air . You can feel it when hold a finger into the airstream. The lower brass retention valve should keep the rest of the pressure inside .

 

​​after hitting 160 k miles, I was replacing front end parts and discovered oil leakage on my one of my coil-overs. Replacements from Rock Auto included a new resister, so I suspect they come standard when you order a kit.

 

Hello, so sorry for the delayed response. At least I can give a 2200 mile update. Love the Strut Master kit and no regrets. Ok one thing. I hear creaking from the rear suspension so I might need to lube suspension points? minor points I'll get to eventually.

I hnestly forget that I change to strutmasters sometimes, but maybe im not too picky. There are no suspension faults showing. The kit comes with an override to the ASM module in located behind the rear seat. You just need to cut into the wiring. Not hard.

Just my humble 2 cents.

 

Thanks for the update, glad to hear it comes with something to disable any warning lights.

As for the creak in the rear suspension, might not have anything to do with the new kit. My car had 40k when I bought it a couple years back and nearly all of the suspension boots were torn/gone. Joints were still decent for the most part, but the creaking was awful. I lubed everything really well with a needle fitting on my grease gun and 20k miles later its still silent as can be. I actually have all new arms for the car but it still rides so well and doesn't make any noise I'll just put off replacing them until something goes bad.

 

Do you have a link to the exact kit you purchased?

 

Yes a link would be great. Did you end up doing the work yourself? I feel I have a compressor going bad, but I have been told the front struts are leaking as well. My jag looks great but I seem to have several suspension issues to deal with or fund as well as an oil leak probably from head gasket or timing cover. Not sure how much I want to put into her, but she looks very good and drives well enough for a 20 year old car...