I'm getting ready to pull my front air shocks to replace my upper control arms. Anything special I should do for the air suspension? Pull fuse, disconnect battery, bleed all air, etc???

Can I jack one front side of my car at a time yo complete this or do I have to jack both sides and support them at once?

Tks
2005 VDP

 

Hi Deepstuff,
Not had to go there myself yet, but forum member Wolvesfan did a very good write up that he posted on 18th April this year, when he rebuilt all four corners of his car.
Here is a link to that thread which contains a PDF of his overall task.
Hope that gives you some valuable information.
https://www.jaguarforums.com/forum/x...ebuild-269067/

 

@h2o2steam - thanks for your kind words.

@Deepstuff - I lifted the car on my quickjacks to keep it as 'square' as possible and reduce any twisting or flexing of the chassis, so I didn't jack it up, as such, but if I did then I would want to try and keep both sides at the same height during the work. Regarding removing the air springs, you have no option but to remove the airline connections (plus the four nuts and the sensor connection) from each spring. I think later models only had one sensor connection for the pair but my 04 has one sensor on each air spring. Removing the airline will cause air loss, so it will be a test of your compressor (and perhaps your nerves) when you reconnect Others have posted about issues with the suspension re-raising - some said their cars needed to be driven a short distance but mine reinflated without moving the car, and within a minute or two just from the engine running at idle speed. When you remove the airline, it pays to be take your time. I used a flarenut wrench for better grip/less chance of rounding. As you will see from my write up, some of the upper control arm nuts (2 out of 4) are awkward to get to but it can be done with (in my case) socket joints and extensions. When reconnecting your sensors, again, take your time, as there is a specific orientation - don't force them. Good luck!

Edit: Before lifting the car, I removed the negative terminal from the battery to prevent the suspension from getting confused. I know it has a 'jacking mode' but I just disconnected the whole electrical system. Worked for me. Don't reconnect until the car is back on the ground.

Cheers,

Steve.

 

Forgot to mention .... don't tighten up the upper control arm nuts until the car is back on the ground. If you tighten them up while the car is in the air then the upper control arm bushings will be under even more tension when the car is back on the ground.

 

Are the bolts accessible with the wheels on? I saw in your write up thar u measures from hub center to fender? How accurate dies this have to be? If accessible I'll measure from garage floor. Looking at car i think ill have to do it with wheel removed but ill see if torque wrench will fit later - doubt it!
Another question. Did you like and recommend the wheel center caps that you bought?

 

Ratcheting, flexable, combination, wrenches. .

 

Hopefully I am understanding the context of your first question here ,,, if you mean to get a wrench on the bolts - which as you probably know are in the wheel arch - to hold them while you loosen the nuts - which, also as you probably know, are either side of the strut tower under the hood - I don't think there would be enough clearance between the tire and the fender to position yourself (or if there was then it would still be more awkward than if you just took the wheel off, IMO). I did all my work with the wheels off (and TBH I can't see how you would remove the air spring without removing the wheels - and you need to remove the air spring to be able to remove the UCA bolts so you can remove the old UCA and replace it.

I wasn't millimeter perfect about measuring the ride height. I was fine with a +/- 1/4 inch gap (I tried to be as level with the tape measure reading as I could but just eyeballed it - nothing scientific about the measurement. Just take your time jacking up each corner - there is quite some distance between the lowest point with all the wheel assembly and control arms hanging down, and the height you need to jack up to, to get to ride height, if that makes sense. And it pays to be slow and steady - this part (together with waiting to see if the car would rise up again after I'd finished) was the most nervy part for me, so make sure whatever you are jacking up with is secure against whatever you are contacting on the wheel assembly.

I would recommend measuring from the wheel center to the top/middle of the wheel arch, as that will be more accurate than using any other reference point, IMO, Measuring from the wheel center can be done with the wheel off or on the car - if it's off then measure from the center of the wheel hub. If it's on then measure from the center of the wheel center cap. I measured from the center of the wheel hub, since my wheels were off. I'm sure there would be some marginal difference between measuring from the wheel hub vs the center cap of the wheel if the wheel was on but we aren't working on Formula 1 cars

Would I recommend the wheel center caps? For the money, absolutely! They are a little loose when you press them in but as others and I have done, use some clear silicone sealant on the inside of the wheel to hold it in place - doesn't look very tidy if you look from the back of the wheel but you can't see anything from the outside and it seems to work just fine (and you can easily remove the silicone at a later date if you needed to).

Probably still worth getting an alignment after changing the UCAs - they don't seem like they would affect the alignment as much as if you changed the lowers, but after any suspension work it is always a good idea to get an alignment, IMO.

HTH!

Cheers,

Steve.