The differential is a geared mechanism located between
the driving axles of a vehicle. [t rotates the driving axles
at different speeds when the vehicle is turning a comer
(Figure 38-21).It also allows both axles to tum at the
same speed when the vehicle is moving in a straight line.
The drive axle assembly directs drive line torque to the vehicle's
drive wheels. The gear ratio of the drive axle's ring
and pinion gears is used to increase torque. The differential
serves to establish a state of balance between the
forces between the drive wheels and-allows the drive
wheels to tum at different speeds when the vehicle
changes direction.
On a FWD car or truck, the differential is normally
an integral part of the transaxle assembly located at the
front of the vehicle. Transaxle design and operation depends
on whether the engine is mounted transversely
or longitudinally. With a transversely mounted engine,
the crankshaft center line and drive axle are on the same
plane. With a longitudinally mounted power plant, the
differential must change the power flow 90 degrees.
On RWD vehicles, the differential is located in the
rear axle housing or carrier. The drive shaft connects