Question about what e53s came with full air suspension

[Ricky Bobby]

Not sure on the front bags as I never replaced the rears, however I do have Arnott replacement struts on my X.

I am one of those weird ones that is 2003, with options S221A and S226A. I was under the impression from a thread we had some time back that the "Sport" rear bags Arnott sells cross reference a BMW part number for an X5 that has sport package option S226A, but has only rear self-leveling (normal coil springs/struts) in front.

We came to a conclusion in that thread that no matter your option package if you had S226A sport or not, if you had S221A EHCII full air suspension and were replacing the rear bags you needed the comfort ones for the full articulation of the air suspension.


I enjoy having one of the "rare" package combos around these parts so have been enjoying educating myself over the past 2 years (and thank you Qsilver as always for the knowledge, I knew EHCII debuted in 2002!)

[4.8isX5]

Interesting point about the full articulation ricky, i remember seeing that as well..

But now i have a different POV on it, while the may not provide as much range in height as for example the comfort ones, the comfort ones do look bigger overall then the sport.

So now if you put sport bags up front, and in the rear ( i believe they made sport bags up front yes? didnt check cause writing this from phone) i believe they would bolt up/install fine into the 4.8, i dont care for the offroad portion of it at all, but my thinking is

Since comfort ones seem to be overall bigger, and sport smaller, meaning like me and my other buddies who run our X's low,

The sport ones would retain a higher pressure of air in them if at the same height of the comfort bags if you get what im saying, since basically less pressure = lower height, but thats not always good as well cause you dont retain the "sportness" as you do with for example harder coilover springs..

I hope thats easy to understand lol, basically saying both X's lowered, the one with comfort bags will have less pressure and easier to bottom out, versus a smaller bag at the same height will have more pressure in it just cause theres less room for the air to go.

[Ricky Bobby]

Originally Posted by 4.8isX5

Interesting point about the full articulation ricky, i remember seeing that as well..

But now i have a different POV on it, while the may not provide as much range in height as for example the comfort ones, the comfort ones do look bigger overall then the sport.

So now if you put sport bags up front, and in the rear ( i believe they made sport bags up front yes? didnt check cause writing this from phone) i believe they would bolt up/install fine into the 4.8, i dont care for the offroad portion of it at all, but my thinking is

Since comfort ones seem to be overall bigger, and sport smaller, meaning like me and my other buddies who run our X's low,

The sport ones would retain a higher pressure of air in them if at the same height of the comfort bags if you get what im saying, since basically less pressure = lower height, but thats not always good as well cause you dont retain the "sportness" as you do with for example harder coilover springs..

I hope thats easy to understand lol, basically saying both X's lowered, the one with comfort bags will have less pressure and easier to bottom out, versus a smaller bag at the same height will have more pressure in it just cause theres less room for the air to go.

Your point of thinking is right regarding when you lower your X with DIS or what have you, you are lowering the pressure in the bags and is actually making the suspension more "cushy", as opposed to stiffening up like a progressive coilover setup.

As far as I know you cannot take the rear fitment "sport springs" and fit them onto our factory air struts as the front and rear bags are different designs, mounting fitments etc. If you want to be able to lower your factory air ride but yet keep the ride stiff and sporty, you would need to go aftermarket, most likely with Accu-air or something similar.

X5SND has gone with a custom air setup on his X, using factory 4.8/full air suspension bags on all 4 corners, however, his management system is better so I'm under the impression he is able to lower the suspension yet have it a bit stiffer than stock, you'd have to ask him though about his setup, he did a build thread a while back:

http://www.xoutpost.com/bmw-related-...hello-air.html

[oztme]

For the record: my 2005 E53 3.0d sport has no airbags at all. It was an option, but not very popular here in oz.

I want to put BCRacing coilovers on, along with airbags on the rear so I can level the car out when putting heavy loads in the back.

Question: does anyone know if the mount points for struts & rear coilovers are exactly the same on E53's from factory, regardless of sport/normal and airbags vs springs?

I'm about to do opposite of what most people do: going from Sport springs, to airbags on the rear, and coilovers all around. I will use manual inflation of air bags when I load the rear of the car up.. A bit worried that the BC Racing coilovers will be made for different mount points than on my sport 3.0d.

Advice please chaps?

[4.8isX5]

Yeah i was just trying to see if maybe could just do something with the bags to improve it.

We have the other silver 4.8is in our group like mine and he has aftermarket air management, so at the height he is, with the factory bmw system, its basically aired out, but his still has air etc, easier to adjust and works differently then bmw factory sys.

[Ricky Bobby]

Originally Posted by 4.8isX5

Yeah i was just trying to see if maybe could just do something with the bags to improve it.

We have the other silver 4.8is in our group like mine and he has aftermarket air management, so at the height he is, with the factory bmw system, its basically aired out, but his still has air etc, easier to adjust and works differently then bmw factory sys.

Basically the Arnott/BMW bags are good, its just the management with the air tank, etc, that needs tweaking, you said it right there with the other guy in your group (I've seen pics of his X before, he's Mike's boy right?) and its all about the management system, tank size, compressor, etc. If you're good at that kind of stuff its definitely doable, I don't run my X slammed though (I'm only about 1/2" lower than stock sport height), just drop it to lowered view for pics

[X5SND]

I explained it to another member in some other thread a while back (I can't recall where) but basically, as you go lower with the factory BMW setup you need to decrease the overall compressible volume to speed up the reaction time of the system. Unfortunately the way BMW designed their air set up makes that task anything but easy.

The other situation/limiting factor we face is that our vehicles use MacPherson struts up front.....had BMW designed the E53 with double wishbones we would have a PLETHORA of possibilities.

The ideal route (Ive pondered it for a while) would be to talk to RideTech and ask them what would the possibilities be of doing a Shockwave Select air strut. They already make components we could use for the rears, so that shouldn't be a huge issue. This road would get us electronically adjustable dampers coupled with bags designed around our lower ride height....win, win.

[4.8isX5]

Yeah i was just trying to see if maybe could just do something with the bags to improve it.

We have the other silver 4.8is in our group like mine and he has aftermarket air management, so at the height he is, with the factory bmw system, its basically aired out, but his still has air etc, easier to adjust and works differently then bmw factory sys.

[smarkwilson]

has anyone ever added front air suspension to there X and maybe aftermarket control of the system? I have rear air only and want to add front for 4 corner but control manual from in side or remote system

[Kristophe]

I was pleasantly surprised to recently discover that the mystery connector in my spare tire area (as well as one for a module in the battery compartment between the PDC and towing modules) on my 2001 3.0 non-sport is pre-wiring for rear air suspension. I suspect it was part of the level 3 option(s) harness that I have.