Based on a non ADC Model the rear gear ratio over drives the front to prevent the front hub from locking in Four WD until the rears slip 1/5th of a turn. When the ADC is engaged all four wheels have engine braking. Do all four wheels rotate at the same speed or are they still subject to the gear ratio differences between the front and rear diffs? Just trying to wrap my head around it.

Totun

 

I would say there is a differance, as the rears just start to slide the front will kick in and hold back as needed, this way you you can easily steer. It works so fast you can barely tell its working. Just switch into 2wd and then you'll notice the differance.