My understanding is that the rear gets more torque than the front. I have not counted the gear teeth nor measured the diameters of the planetary gearset, but I assume the split is around 60% rear. I have not read any weight distribution data, I dont think that 60% is in the front tho. that sounds high.

BMW tries to get all its cars weight balanced 50:50. Their awd transfer case gives more torque to the rear to give the car a rear wheel drive feel. It also makes sense that when you accelerate, the weight changes and more weight is on the rear wheels.

Also of significance is that 02 and o3 x types have a viscous coupling in the tranfer case to limit slip front to rear. the newer cars, and any with a rebuilt TC will not have the VC.

 

you are confusing things here.. the 60:40 is the torque split, done via a planetary differential. all shafts turn at the same speed, unless one is slipping. the VC only comes into play when there is wheel slip. when all wheel are rolling along, the VC is dead weight.

 

Sorry to have to quote you Buck, but I wanted to point out:

good write up, and helpful pics, I would like to propose that there are 2 fairly large errors on this.
Firstly the drain plug does not drain 550ml. It drains about 400ml.

Secondly, The description of the planetary gear set is not correct, the concentric shafts shafts do not turn at different speeds when the car is driving in a straight line.