Drive line torque is evenly divided between the two rear
drive axle shafts by the differential. As long as the tires grip the road, providing a resistance to turning, the drive train
forces the vehicle forward.:When one tire encounters
a slippery spot on the road, it loses traction,
resistance to rotation drops, and the wheel begins to spin.
Because resistance has dropped, the torque delivered to
both drive wheels changes. The wheel with good traction
is no longer driven. [f the vehicle is stationary in this situation,
only the wheel over the slippery spot rotates.
When this is occurring, the differential case is driving the
differential pinion gears around the stationary side gear.