3
X5 Updates
Two Axle Air Suspension
Purpose of the System
The two axle air suspension system (EHC2) offers advantages over the single-axle air sus-
pension with respect to ride comfort and off-road capability.
Lowering the entire body makes it easier to enter, exit, load and unload the vehicle.
The vehicle's off-road capability was improved by providing the possibility for increasing the
ground clearance of the body.
The driver can now choose between three different ride levels which can be set with a rock-
er switch, as required. Automatic ride-height control for payload compensation and
automatic inclination compensation continue to be fitted.
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The automatic payload compensation facility for the single-axle air suspension did not per-
mit driver control. The driver could not actively control the system to make it easier to enter
and exit or load the vehicle.
Ride level was compensated via the rear axle only.
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The new system allows the ride-height control system to be controlled actively by the dri-
ver.
The twin axle air suspension allows both axles to be lowered evenly and in parallel.
As a result, it is easier for the occupants to enter, exit, load and unload the vehicle.
History
BMW previously supplied ride-height control systems as both optional equipment and, in
part, as standard equipment on the 7 Series - E23/E32(not in the US market), 6 Series -
E24 (L6/M6) and 5 Series - E28 (M5). On the E39, the load of the complete rear axle was
born for the first time by air suspension in combination with the optional ride height control
system. The system was controlled automatically under all operation conditions, and there
was no possibility for driver intervention on the X5, the rear axle previously had single axle
air suspension only. The air supply unit and the control unit were adopted from the E39. The
air springs were adapted to the X5.
There is a standard version and a sports version.
The ride-height control system (EHC) was supplied as standard in combination with the
M62 engine and is available as an optional extra in combination with the M54 engine.
EHC2 is optional on both the M62 and M54 versions of the X5 and not available on the
4.6is X5.
