What kind of air suspension do I have?
 

Guys I'm a little lost
I thought all 4.8is come with EHC II but I have this pump style under the spare:
BMW E53 X5 N62 4.8L Suspension View All - 37226787617 - Air Supply Pump - ES#254906

Does that mean it's only got the rear self level susp?

The car is at the dealership trying to figure out the self level susp inactive message...they changed the rear bags now the pump...good thing it's 0$ on my part..

I'm not sure why the sight of the air pump supply unit below the cargo area makes you think you don't have EHC II (dual axle self leveling)...because the air has to come from somewhere. :)

Checking the actual BMW part nbr would provide you with better or conclusive evidence. If you look up the air supply unit in the BMW part database...you'll see the specific 11 digit BMW part nbrs for each set-up:

1. 37226787616 - EHC I (single axle self leveling system) air supply unit
2. 37226787617 - EHC II (dual axle self leveling system) air supply unit

See the illustration below and take note of #1 in the EHC II illustration...it shows the rounded air supply unit for the EHC II system. The illustration of the EHC II system is drawn in smaller "scale"...but that is due to it being more expansive since it covers the front axle, too...thus the drawing is smaller so that it fits within the same size space as EHC I (single axle system):


Do you also have the switch on the dash (left of the steering wheel)? If you do, only the EHC II system has this switch...the single axle rear self leveling doesn't have this switch:

Hmm okay that makes sense
I asked because in the link provided is states that that pump is only for EHC I
And the dealer said they only replaced the rear bags and that got me thinking I have the first generation suspension type
But thanks Q for the detailed answer!!

You're right....ECS Tuning has the part nbr identified incorrectly as being for the single axle system. And when you search using the single axle part nbr, it comes up but there's no description.

This is another reason I always double check by looking up the part nbr using at least 2 part databases (my favs are realoem.com & bmwfans.info) which sometimes reveals that a part nbr has been superseded...and helps wade through misinformation that can occur with aftermarket vendors & eBay sellers etc.

Glad we got it sorted out though. :)