Rear suspension drops, dealer says not airbags?

[ptr727]

My 2016 X5 50i has been acting up and the rear suspension would just randomly (3 times in 2 weeks) drop after parking, power up, compressor on, takes a couple minutes to be level again.

I believe my car does not have an air suspension, but 3rd row with DSC, and I understand also uses air bags for leveling.

Dealer wanted to repro before investigating, car stood 3 days in various incline positions but no drop. They wanted to give up due to no repro, I insisted they do an airbag leak test even if no repro, they did, said no airbag leaks.

They suspect but cannot confirm it is the compressor valve as it does not leak on demand, but compressor $$ more than airbags.

Left car there the long weekend, they will check again on Tuesday if dropped, not that it matters, if it drops they've only confirmed what I told them, not the cause.

Any other diagnostics I can ask for to confirm?
Is it common for the compressor to leak before the airbags?

P.s. Oh, and kicker is my extended warranty ran out two weeks prior to the sag starting

[cfm56d7b]

How many miles does your car have?

BMW X5 rear air springs (the official part name) are a known problem area. The rear air springs on our family 2015 X5 were replaced at 35K miles. The same symptoms as yours. The compressor is still OK.

With remote diagnostics being what they are ... the symptoms you describe suggest:

- The rear air spring began to leak lowering the suspension
- The sensor worked and told the compressor to activate
- The compressor also worked and provided enough air

The rear air springs would probably be the first set of parts to be replaced. If cost is an issue, FCP Euro sells aftermarket rear air springs made by Arnott. Much cheaper.

[ptr727]

Low miles, 36K.
I'd rather replace both airbags than the compressor, and OEM is fine.

I am just a bit concerned about the dealer's approach to troubleshooting, i.e. seems like a well known problem, I'd have tested for airbag leaks first, why bother trying to repro, the diagnostics would have been the same regardless?

[ptr727]

Just an update, I took the car without making any repairs and only paid for the investigation.
I did not want to "parts canon" without an actual leak being detected.
If the issue increases in frequency I'll try to have it leak tested again.

[acmurda]

Always start with replacing the bags. Cheapest and easiest and almost always the culprit. Bags have creases where they fold, that's where the cracks form...those cracks only leak when the bag is in a certain position. There is absolutely no way of visually checking for bad bags without removing them from the vehicle. I've changed several sets on several vehicles.