At 99,600 miles (US), my '06 is giving me Level Control Malfunction messages. One reads: Ride Comfort May Be Reduced And the other: Ground Clearance Reduced.

From the outside, the rear end looks normal. I've seen dragging rears on AirMatic cars before and mine looks nothing like that. Garage says three stored faults match BMW's SB for internal compressor failure with a $1,500 USD cost to replace the compressor.

That sounds like dealership prices to me. So far, it only seems that the compressor needs replacing- no cracked or split lines/struts. So...is anyone familiar with this SB? What have others paid at Indy garages for this replacement?

Searching around (albeit quickly) hasn't revealed anything relevant other than compressor costs a few years ago in Pounds Sterling.

 

Try reading this thread for some more info:
https://5series.net/forums/e61-touri...ailures-77514/

 

Thank you, InsipidMonkey. I was under a time crunch earlier but it has now been resolved. It seems that there are a number of reasons that cause our rear to drag. Apparently part of the initial quote was for a BMW-branded compressor from BMW parts.

Ordering the Arnott pump was much cheaper (by nearly $600) for the same part but without BMW's logo emblazoned on it.

The bulletin was printed out for me. It seems that it had to do with timing problems and the compressor being unable to inflate the bags in the alloted time. I am still not clear why they call it a failure as the compressor is still filling the bags without sag. The lines are still good at nearly 100k miles, which is impressive.