When that startes happening the are going. (At least one of them). Go ahead and replace one or both of them now. When my driver side went I just replaced it, but the passenger side went 6 months later.
It's am easy job and if it completely goes while you're out driving it leads to the most uncomfortable ride. As in, not safe to drive.

You may have a leak in the airbag. I would do the soapy water test to see if you have any visible leaks. I would find out right away and replace the airbag before your compressor goes out, which happened to me because i took forever to replace my airbag suspension.

is it normal for the compressor to kick in every morning even without sagging in the rear?

Mine did. Shocks lose air before they sag.

Makes perfect sens to me.

Remember that sometimes the thing can leak quicker then others.
Remember that compressor will come on every time it detects car level is off kilter.

Good luck.

Just wanted to say thanks for this write up. I did this today step by step using this tech tip and it went flawlessly.

Couple of things to add. I have the 3rd row of seats and it's not easy to removing stuff inside to get be able to see the color of the top. This wasnt actually necessary in the end anyway. It is true that you will spend more time getting it up in the air than you will actually replacing the air springs.

Thanks!!

So I was installing one of the Arnott bags today and everything was going smoothly until I tried to clip the bottom of the bag into the arm/perch. I couldn't stretch it enough, so I put a jack under the arm and raised it up a bit. I though both clips were locked in, but when I slowly lowered the arm, one of the clips broke off.

First off, is this new bag trashed now?

Second, how are you guys getting the bottom of these things seated?

I'll try to upload some pics if it helps.

That sucks! I had to stretch the bags down pretty hard to get them to clip. Frankly even once installed they are 'loosely' in place.

I'm no expert but I don't think it matters much anyway. The weight of the car is always putting downforce on the bag to perch anyways. I think that if you can keep them lined up while lowering it may not matter.

Yes, it does suck.

I just went ahead and ordered a new bag and set up a return for the broken one. I agree that the pressure of the bag would probably keep it in place, but I don't like knowing that if the car is lifted for service, the bottom could come out of the perch/housing. Then who knows? Maybe over inflate or not go back into the housing, etc. I also wouldn't feel right about selling the car, which we will probably do within a year or so.

Good to know that it fit in "loosely". I honestly don't think the two clips on the bottom of the bag were pushing out enough to secure the bag to the perch/housing. If that the case with the replacement bag, I'll just lower the car after installation and guide the bottom of the bag into the housing.

My only issue now, which I'll call Arnott about, is how do I get the air line out of the bag? It's self securing, unlike the OE BMW bag.

Fun times.

Oh, I'm also really surprised that these two little plastic clips on the bottom of the air bag are strong enough to hold the weight of the wheel/tire/arm when the car is lifted off the ground.

either our pump or airbags are shot.

slammed when parked for more than an hour.

we have the sports package suspension (4.8)

should we go with aftermarket or BMW bags?

I notice BMW has different part numbers for SP.

I don't mind paying the $200 difference (2 bags) if they will fit better and clip on easier.