X Series E83 X3 2.0d (N47) OFFRD
individual wheels are specifically braked.
The drive torque is delivered to the axle that has better traction when road conditions change, such as on snow, ice
or a loose road surface.
The transfer cases are matched to vehicles as follows:
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E53: ATC 500 transfer case
(ATC = Active Torque Control)
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E70: ATC 700 transfer case
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E83: ATC 400 transfer case
The transfer cases differ in the following points:
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Different number of plates in the multi-plate clutches
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Different clearance between the input and output shafts to the front axle
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Propeller shaft inserted into the front axle differential on the E53, E70, and flange-mounted on the E83
The transfer case is designed to be stronger on the E53, E70 in order to match the higher engine torques.
The advantages:
xDrive delivers the following advantages through demand-oriented drive torque distribution:
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Outstanding driving stability fully up to the limit range
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Optimal forward momentum
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Excellent traction in all road situations
xDrive is standard equipment on the E70, E83 and on the E53 from October 2003 with the new model version.
Brief description of components
xDrive consists of the following components:
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Transfer case with multi-plate clutch
The electronically controlled multi-plate clutch is housed in the transfer case. The multi-plate clutch distributes
the drive torque smoothly and as required between the front and rear axles.
[more ...]
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VTG actuator motor with incremental sensor and classification resistor
The VTG actuator motor (VTG: transfer case) opens and closes the multi-plate clutch. The location of the
actuator motor shaft and the adjustment rate are detected by the incremental sensor.
The classification resistor ensures that mechanical tolerances in the transfer case are considered. Optimum
function is thus ensured.
[more ...]
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Actuator lever
The actuator lever converts the rotational motion of the VTG actuator motor into an axial motion. [more ...]
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VTG control unit
The VTG control unit regulates the locking torque at the multi-plate clutch in the transfer case in response to the
following factors:
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Demand for required locking torque (comes from the DSC control unit)
•
Condition of the transmission oil (calculated in the VTG control unit)
•
Multi-plate clutch wear (calculated in the VTG control unit)
•
Load on VTG actuator motor (calculated in the VTG control unit)
SBT xDrive E53, E70, E83
BMW AG - TIS
07.02.2013 00:10
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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