from prolonged spinning of one wheel. This is especially
true if the spinning wheel suddenly has traction. The
shock of the sudden traction can cause severe damage to
the drive axle assembly.
To overcome these problems, differential manufacturers
have developed the limited-slip differential (LSD).
Limited-slip differentials are manufactured under such
names as sure-grip, no-spin, positraction, or equal-lock.
Some vehicles use a viscous clutch in their limited-slip
drive axles. These units are predominantly used in 4WD
vehicles and are discussed in Chapter 41.