front differential BMW X5 2002 E53 Workshop Manual

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Drivetrain
The transfer case, driveshafts, final drives and half shafts make up the drivetrain assembly.
The transfer case is always mounted in the same position on the X5. This applies to other
markets and future models that will utilize different transmissions for different engine con-
figurations. With these models, the transmission tail shafts will be modified to match up with
the transfer case.
The rear driveshaft is a two piece unit using a center bearing, while the front drive shaft is
a single piece that is splined to the transfer case and bolted to the front differential.
The breather vents for both differentials and the transfer case are mounted higher up on the
chassis to prevent water from entering if the vehicle is driven off road through water. The
front breather passes up into the engine compartment and is mounted under the left side
ignition coil cover. The rear breather passes along the under side of the body and is mount-
ed behind the left side wheel arch cover. The breather vent for the transfer case is mount-
ed up high in the driveshaft tunnel.
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Drivetrain-Final Drives
The final drives for the front and rear axles are conventional differentials. The DSC system
provides anti-spin/slip control for both the front and rear axles on the X5.
The rear differential is the HAG 188K
(compact) unit with a ratio of 3.64 : 1
The front differential is the VAG 174
unit with a ratio of 3.64 : 1.
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Rear Suspension
The rear suspension is the “intragal” multi-link design taken from the E38/E39 vehicles.
Several components AER made from aluminum to erduce the unsprung weight. The X5
with the M62TU engine uses the EHC (air spring) suspension system. The EHC functions
the same as the E39 Sport Wagon with only minor differences to the components and lay-
out of the system. The X5 with the M54 engine will use standard springs in the rear with the
EHC system as an option. The rear struts on the X5 are mounted to the body instead of
the sub-frame.
The rear axle sub-frame is mounted to the body through four bushings (larger than E38) for
increased load and comfort. The rear differential is mounted through three rubber bushings
two in the front and one hydromount in the rear. The wheel bearings are similar to the E39
but incorporate different seals - designed for off-road use.
New special tools are available for adjusting the rear suspension due to the limited space.
Rear Axle Technical Data
Track: 1576mm
Toe In: 18 Feet
Camber 1 Degree 50 Feet