Quote:
Originally Posted by TiAgX5
I don't see why seeing how all modern cars/trucks are required to have braking systems that can overcome the max torque produced by their powerplants.
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Because it was based on the the legacy AWD system that had been in use since the early iX cars from the 80's. On the early X5's, this is a planetary gearing that fixes the amount of TQ/power to the front or rear axle. In the early X's- 38 Front:62 Rear. Front rear power/TQ transfer is not programmed at all in the early X5's. It's fixed by the gears.
Xdrive uses a multiplate clutch system on the output side of the transmission that allows the system to modulate/vary the amount of TQ between the front and rear axles. XDrive computer control is able to activate this clutch within something like 1/10 of a second for up to 100% to the front or rear axle. The drive is normally split at 40F:60R for XDrive cars.
It is a significant difference from the early/non facelift cars. XDrive is one of the main reasons I bought one in 2004.