Rear suspension drooping. Air bag or???

[wsmeyer]

I've searched and read all the threads I could find but I'm still a little confused. My 2008 X5 with 3rd row seats drops down in the back after sitting for a while. Unlike most of the threads I've found, mine droops equally on both sides.

That leads me to three possibilities:

A. one bag is leaking and letting the air out of the whole system. But if that's the case why do some people only report one side drooping. Wouldn't both sides always deflate equally?

B. The check valve in the pump is bad and the air is leaking out there.

C. One of the air lines is leaking. I haven't seen a thread where this turned out to be the problem so maybe this is the least likely?

Hoping to get some guidance on figuring out what needs to be replaced.

[gregg3gs]

Can you drive the truck on ramps and spray both bags with soap?

What if both air springs are bad?

[jerryx5]

My 08 X5 w/ 82k miles was dropping about 1-2 inches evenly overnight. Ended up replacing both air bags.

[wsmeyer]

Thanks for the input guys. Not sure why I didn't think of checking them with some soapy water.

I looked at them in daylight and they didn't look too bad but I looked at them again last night in my dim garage with a bright flashlight and this is what I saw:



So now I think I'm just going to replace both as even if they really aren't leaking they don't look like they have much life left on them.

I'll report back after the operation.

[gregg3gs]

That is what my bag looked like too. The damage may be on the inside of the bag as well. I mean on the part that is rolled on the inward side.

I posted a DIY a while back, let me know if you want a link.