DIY Guide, Rear air spring replacement

[Bch06]

Originally Posted by Mr.47

Air suspension leaks are no fun my first encounter was back in January 2018, when my car would seldomly start to sag in the rear, especially in the left side, I ignored it at first...however as months passed it become more and more apparent and frequent and now both sides are sagging, there was even damage to the side wheel flairs. So it was time to resolve this issue for good. Its best to rectify this problem asap, as leaving it unresolved in the long run may cause the air pump to burnout and or cause premature wear on suspension parts.




The culprit a 70k miles 4 yrs old air bellow looks like never towed never lifted heavy things and riding on 20 in oem rims, (left) when its not stretched it looks normal but (right) when you begin compress the bellow and stretch it the walls problems begin to show multiple deep cracks on the rubber bellow, this is the reason why air leaks occurs.



***DISCLAIMER***THIS IS AN DIY COMMUNITY GUIDE I'M NOT A PROFESSIONAL AND WILL NOT BE HELD RESPONSIBLE FOR INJURY/DEATH OR PROPERTY DAMAGE BY FOLLOWING THIS GUIDE, IF UNSURE SEEK PROFESSIONAL ADVICE/MECHANIC, OTHERWISE PERFORM AT YOUR OWN RISK***DISCLAIMER***

Tools
Battery charger
ISTA-D
Pair of Air struts ( I got mine at Arnott $160~ +shipping/each)
10mm Wrench
17 socket
Various ratchet and breaker bar

1) USE SAFETY!!! ALWAYS USE JACK STANDS TO SUPPORT YOUR VEHICLE, ALSO USE A WHEEL CHOKE ON BOTH FRONT WHEELS, OR CAR WILL ROLL FORWARD WHEN LIFTING!!!!!

Lift up the vehicle you can use the rear axle as jacking point (#3), do not jack up with out something in between the axle and the jack pad (i use a block of wood to prevent marring on the diffrential)





2) After lifting and using appropriate support remove wheel, use 17mm socket, I use a torque multiplier makes things a breeze to remove those lug bolt.



3)After removing the wheel you should be able to see the air strut



4) Now its the time turn on the ignition, hook up your ISTA-D and your battery charger so your vehicle don't go to sleep and you ending up having to start over.



5a) Next before we begin to deflate the strut with ISTA-D, you'll need to remove the fuse for the air pump (Per "ISTA-D") go to the back fuse box (located in the right side panel in trunk) and find 40 amp fuse #110 (see yellow square)



5b) If you look at the fuse chart it says air suspension fuse #110 and #135 and you accidentally pulled fuse #135 (5 amp) you will get this nice little warning, don't worry, just turn off the ignition put the fuse back in and turn on the ignition back and you'll be good to go. I didn't know better OOPS



6a) Once you pulled the fuse its time to deflate with ISTA-D.
Go to VEHICLE MANAGEMENT>SERVICE FUNCTION>+Electronic Ride Height Control > Filling and Discharging air from air bellows > ABL Electronic ride height control (EHC) Filling and draining



6b) Next prompt it ask you if your bleeding or filling. Select Bleed of the air bellows (bottom)



6c) Next prompt, Make sure you've done the precondition check list, failure to do so will cause it to stop and you'll have to redo. Click Yes when ready. NOTE: You'll have 3 consecutive cycles before it automatically invoke a 5 min cool down of the release valve relay, it make take more then 1 cycle to deflate completely (it took me 2 cycles)



6d) Next Prompt, The air suspension will cycle the release valve and both sides will drain NOTE: NEVER LET DOWN THE VEHICLE IN DEFLATE STATE OR DAMAGE TO SUSPENSION WILL OCCUR!





7) You should be able to observe the strut contracting/deflating, also squeeze the strut bellow it should have a soft sponge like consistency, if it difficult to squeeze another deflate cycle is needed.





8) Removing the air strut, first thing is you'll need to remove the bottom squeeze tabs, a channel lock pliers or a screw drive to squeeze in the squeeze tabs, and remove from its mounting socket.



9) The bellow has 2 tabs on top that alined and twisted on to secure, to do so just rotate the entire bellow counter-clockwise, it should not take much effort to do so (if deflated fully) and only about < 1/2 turn.



10) Next Remove the air line from the bellow, you'll need to rotate the the strut top side facing outside/you this can be a bit tricky but its not bad then use a 10 mm wrench to remove the nut from strut (the line is red because i forgot to take pic and was working on the other side))



11) Remove the air line harware, you may need to use a screwdriver to pry the brass line holder/seal, check line for damage, clean and set aside.






13) Remove the strut,



OBJECTIVE NOTE arnott is diffrent from OEM in terms of the TOP part, it has a larger top clamp and the top metal clamp is exposed, vs the OEM with smaller top with the clamp recessed into the rubber bellow fold,





14) Next you'll need to swap over the dust cap from the oem to the new one, be sure you align the air line hole on the dust cover to the strut bellow.






15) Insert air line, besure to push in as far in or up to the white line, mine been arnott has a gap on the white line, i could not push in further.



16) Installation and secure, with the air line installed you have to wrestle it in it can be tricky but it's doable, start with the top part facing you, slide it in and slowly rotate the up right just watch out for the air line make sure its not kinked or twisted up. After its up right, you'll need to alight with the tabs by feel, just slowly rotate the bellow with slight upward trust and it should plop right in when you've aligned tabs correctly then slowly/gentely turn the bellow clockwise further more until it stops, and finally pull the bottom bellow down to its securing socket till it clicks and stays in place it may take some grunt to pull it down.



17) Check the air line and make sure it secure to its clips and make sure its not obstructing or kinked, Reinstall the wheel and torque lug bolts to 105 lb/ft and repeat steps 3 & 7-16 for the other side. DO NOT LET THE JACK DOWN WITHOUT REFILLING THE BELLOWS WITH AIR, SUSPENSION DAMAGE WILL OCCUR!

18) After completing the other side, reinstall fuse #110 40 amp



19) In ISTA-D, if you're still in the Bleed option, it will prompt you to perform another bleed, Select No



19b) In ISTA-D Go to VEHICLE MANAGEMENT>SERVICE FUNCTION>+Electronic Ride Height Control > Filling and Discharging air from air bellows > ABL Electronic ride height control (EHC) Filling and draining



19c) Next prompt ask you for Bleed or Fill, select Fill (top)



19d) Next prompt, there will a prerequisite checklist before performing fill function, check yes and hit continue when ready.



19e) Next Prompt, the ISTA-D will fill up the air bellow till it has reached maximum pressure will take about 20-30 seconds, once finished there will be "End of service function" hit close and that's it for ISTA-D



20) Slowly lower the vehicle and you're done, now it make take a while for it to settle down, a quick drive and it will come down to normal height and you'll never have to deal with any more saggy rear ends!!!

Thanks, any idea why my ista is not deflating? I even unplugged the compressor fuse but it still doesn’t deflates, what triggers the deflate process?

[fortresskanada]

Yeah these air struts don't last very long 40k-70k miles or around 4 years before the rubber fails, but it appeared that it was already failing before i acquired this car at in 2017 at 60k miles, the left rear side fender arch has some ripple damage from the tire contacting it.[/QUOTE]

Do the Arnott ones last longer than the factory ones?

[TheMane]

Thanks so much for this guide— just followed it for my 2014 f15 (52k miles) which had always sagged a little when parked in the cold but finally couldn’t keep inflated at all after the run of 20degree days last week.

Only hiccup was I didn’t realize you don’t reuse the hardware on the air line after removing it and spent a good 20 minutes trying to figure out how it connects to the new bellows (of course you’re supposed to just throw the old hardware out and push the bare line into the new unit).

Also my first time using ISTA for anything other than reading fault codes. Had to risk doing it without a battery charger but luckily the gods of well charged car batteries must have been looking kindly upon me today.

[kuss]

Good video from Arnott's website on airbag install, avoids INSTA and simple deflation technique.

[triax37]

Thanks again to the OP - I just replaced my rear air springs (while switching from winter to summer tires). Total time, including jacking up the car, was about 1 hour. It's an excellent write-up, and the only thing I could add are a few tips and pictures of how the top portion of the springs mount to the X5. There are two "ears," effectively at 12 o'clock and 7 o'clock. I recommend the following:

1. When the old springs are removed, get your head (or camera) in the suspension area and identify where the spring's "ears" will go.
2. Try to orient the spring to match where the X5's "ear" insertion mounting points are while you're inserting the spring into the hidden area.

Otherwise, good luck! My springs didn't look too bad, and held air when the temperatures were above freezing. But when it was cold, one/both would lose air. I did confirm they were manufactured in 2013.

[Kessler35is]

Has anyone tried baking the Desiccant in the air compressor rather than replacing it?

Curious if the Desiccant that is in from the factory is rechargeable by cooking off the moisture.

[Sabs1815]

OP, thank you for posting this made this DIY a breeze!!!

I tackled this last night took me about 2 hours... The hardest part was getting the new bag positioned back into the top mount because you are doing it blind.
After struggling to get it positioned I decided to open up the trunk carpet and see if the mounting hole is exposed from the top.
To my pleasant surprise it was right there. Once we saw the hole from the top it took seconds to get the new bag positioned and into the hole. Highly recommend opening up the carpet for anyone struggling to get the bag in.

[RED_Y_]

Originally Posted by Kessler35is

Has anyone tried baking the Desiccant in the air compressor rather than replacing it?

Curious if the Desiccant that is in from the factory is rechargeable by cooking off the moisture.

Why? These desiccant beads are dirt cheap.

[genuineguy]

What is the size of air line ? 4mm ?
What is the size of the nut in air lines ? 10mm ?
What is the threading of the nut ? M8 ?? 1/4” ?

[vl_ryandi]

Originally Posted by Bch06

I previously posted here after fixing the air spring issue, however this time the issue is different.

I have an X5 2014 f15 which is showing me an error “chassis function restricted” so I have done the following.

1-Both air bags have been replaced previously 3 months ago when the car dropped down to the ground level.

Recently the car has lifted itself from rear quite high so I did a test on ISTA D which showed me “front left vertical acceleration sensor” so I changed that

Now the chassis function restricted error is still there

I have also used the soapy water to check if the solenoid valve has any leak, however there is no leak.

So I removed the fault codes, and went on a ride however the error came back so this time it’s showing me a different code which is 480DB4 “control time rear left”

NOTE: The car doesn’t deflate with the ista D I have to deflate it manually by disconnecting the air pipes which goes to the Air spring, and also doesn’t inflate when I switch on the car, so I inflated with the ista D and it works.

So my question is do I need to change the air compressor? Or it might be something else? Any suggestions?

Thank you in advance.

Hi, have you solve the 480DB4? My X5 have the same fault code (new air spring and tried 4 used compressor + valve from junkyard).

Thank you

[rayxi330]

Originally Posted by Sabs1815

OP, thank you for posting this made this DIY a breeze!!!

I tackled this last night took me about 2 hours... The hardest part was getting the new bag positioned back into the top mount because you are doing it blind.
After struggling to get it positioned I decided to open up the trunk carpet and see if the mounting hole is exposed from the top.
To my pleasant surprise it was right there. Once we saw the hole from the top it took seconds to get the new bag positioned and into the hole. Highly recommend opening up the carpet for anyone struggling to get the bag in.

I wish I would have thought of that. I changed my air springs in the winter and my hands were wet and cold and I had a hard time lining it up blind. A simple design change on the air springs to add a small lip to fit into the center hole would help a lot. With the top of the spring being flush it's hard to tell if it's not lined up to the hole or not oriented to the tabs, it feels the same either way.

[Abstracted]

Is it true that you can just stab the bag to deflate it instead of doing all the extra work?

[tlow98]

Originally Posted by Abstracted

Is it true that you can just stab the bag to deflate it instead of doing all the extra work?

Yes. It is, however, more dangerous. Also, make sure you have the right replacement otherwise your car won’t be moving until you do…

[Abstracted]

Originally Posted by tlow98

Yes. It is, however, more dangerous. Also, make sure you have the right replacement otherwise your car won’t be moving until you do…

Cool. What's the danger?

[F15_SGM]

can't you just loosen the supply line connected to the compressor to slowly release the air instead?

[tlow98]

Originally Posted by Abstracted

Cool. What's the danger?

It’ll blow dust in your eye or maybe you slip and cut yourself. OSHA stuff :-)

[tlow98]

Originally Posted by osmansiddiqui95

can't you just loosen the supply line connected to the compressor to slowly release the air instead?

That’s generally what the DIYs say to do. BMW TIS tells you use ISTA to release air pressure.

They all accomplish the same thing. The TIS way may save you from throwing a code.

To avoid the system being triggered while you’re in the middle of the DIY it’s mostly just important that you pull the fuse or unplug the compressor or both. This is if you take the non ISTA route.

At least, this is what I have gathered I. Prepping to do this replacement myself.

[CYPER]

Guys, I just bought an X6 2015 with air suspension and it randomly deflates.
The first time it happened overnight and when I started the car the next day it took 1 hour to inflate back to normal.
Next day it happened again, but inflated back in like 10 minutes.
Today again and inflated again 10-15min later.
Never deflated during driving.
They deflate when car is parked for some time, but then inflate later on.

Is this a clear case of faulty air bags or could it be something else?

Thanks.

[tlow98]

More than likely bags shot. Age? Mileage?

[CYPER]

Originally Posted by tlow98

More than likely bags shot. Age? Mileage?

2015
82k kilometres

I have an appoinment with official bmw garage on Tuesday for full diagnostics and visual check.

[Abstracted]

Yuille36 says this about jacking up the X5 at the rear diff:

I wouldn't recommend jacking up your X5M/X6M from the Rear Diff Cooling Fins. Their is a risk of them breaking off, and cracking your rear differential, which would be a very expensive repair.
I would use the (4) jacking points, one on each corner of the vehicle to do this.

Those who have replaced their air springs, have you been using this jack point without issue?

Or do you agree that it's better to jack up a corner at a time?

EDIT: Nevermind. I jacked it without issue at the cooling fins, using a wood plank in between.

[Abstracted]

Originally Posted by tlow98

Yes. It is, however, more dangerous. Also, make sure you have the right replacement otherwise your car won’t be moving until you do…

I didn't experience any danger.

I used a box cutter to slowly cut through the rubber. The cut started a slow leak that I could expand by wiggling it open a bit.

In retrospect, I see no need in using software or taking off body panels and unplug other lines. Manually deflating the bags by cutting them or stabbing them works just fine.