torque apportion

[Bruce]

central diff locked, front axle locked, rear axle locked,

if 3 wheels are freely spinning, the last wheel would take 100% of engine torque

Is it true? I thought it is 25% only

[MY1PATH]

if 3 wheels are freely spinning (both rear 1 front) the last wheel is using ~0% of the engine torque because its all going to the three spinning wheels.
Since the rear is locked no other scenario is possible because the rears spin together.

If all 4 wheels had equal traction it would be ~25% to each wheel.