Axle Shaft Assembly: Description and Operation

Drive axles are flexible shaft assemblies that transmit rotational force from the transaxle to the front wheel assemblies. The axle assembly is made up of an inner and an outer constant-velocity (CV) joint connected to an axle shaft. The inner joint is completely flexible and has the ability of in-and-out movement. The outer joint is also flexible, but cannot move in-and-out.

Two types of inboard joints and one type of outboard joint are used in the drive axle. The outboard joint uses a Rzeppa design and the inner joint uses either a cross groove or a tripot/free-motion design. The inboard end of the right-hand drive axle incorporates a male spline and interlocks with the transaxle gears through the use of barrel-type snap rings. The left-hand inboard shaft attachment to the automatic transaxle uses a female spline which installs over a stub shaft protruding from the transaxle. For trucks, the tripot housing may bolt or "plug in" to the front axle assembly.

The splined shaft end mating with the knuckle and hub assembly is a helical spline which provides a tight pressfit. This assures that no end play will exist between the hub bearing and the drive shaft assembly, for added durability and reduced bearing noise.