The drive axles on front wheel drive vehicles are often called halfshafts. They are flexible shaft assemblies that transmit rotational force from the transaxle to the front wheel assemblies. The halfshaft assembly is made up of an inner and outer Constant-Velocity Joint (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 joints are used in the halfshaft, or drive axle. The outboard joint uses what is called a Rzeppa joint design. The shaft end mating with the steering knuckle/hub uses a helical spline to assure a tight, press-type fit. This design provides a no-end play condition between the hub bearing and the driveshaft. With no end play between the hub bearing and driveshaft assembly, the design provides added durability and reduced bearing noise. The inner joint uses what is known as a Tripot design without an over-extension limitation retainer. The left side halfshaft inboard shaft attachment to the transaxle uses a female spline which installs over a stub shaft protruding from the transaxle. The right side halfshaft uses a male spline and interlocks with the transaxle gears using barrel-type snaprings.
The front halfshaft, or drive axle, assemblies use inboard and outboard joint seals made of a thermoplastic material and clamps made of stainless steel. The thermoplastic material performs well against normal handling and operational wear and conditions. However, it is not strong enough to withstand abusive handling or damage due to objects such as sharp tools or the sharp edge of any surrounding component in the vehicle.
The functions of the seal (most often referred to as the CV-joint boot) are to protect the internal parts of the inboard and outboard joint by protecting the grease from extreme temperatures, stones, dirt, water salt, etc., as well as facilitate the movement of the joints.
The clamps are designed to provide a leak-proof connection at the housing and axle shaft for both the inboard and outboard joints.
The CV-joint boots should be inspected regularly and replace immediately if any defect is found. If the boots are damaged, the special grease will run out, become contaminated and water and dirt will get in an quickly wear out the joint. Refer to Section 1 for CV-boot inspection.