Axle Shaft Assembly: Description and Operation

Wheel Drive Shafts Description and Operation (M15, M76)
Front wheel drive axles are flexible assemblies.

Front wheel drive axles consist of these components:
^ A front wheel drive shaft inner tripot joint.
^ A front wheel drive shaft outer constant velocity joint.
^ A front wheel drive shaft bar.

The front wheel drive shaft bar connects the front wheel drive shaft tripot joint and the front wheel drive shaft constant velocity joint.

The front wheel drive shaft tripot joint is completely flexible axially and laterally.

The front wheel drive shaft constant velocity joint is flexible axially.

Seals And Clamps
The front wheel drive shaft constant velocity joint and the front wheel drive shaft tripot joint seals in the front wheel drive axle are made of a thermoplastic material. The clamps on front wheel drive axle seals are made of stainless steel.

The seals provide these functions:

Protection of the internal parts of the front wheel drive shaft constant velocity joint and the front wheel drive shaft tripot joint.

The seals protect the grease from these sources of damage:
- Harmful atmospheric conditions, such as extreme temperatures or ozone gas.
- Foreign material, such as dirt or water.

^ Allows the angular and the axial movement of the front wheel drive shaft tripot joint.
^ Allows angular movement of the front wheel drive shaft constant velocity joint.

Important: Protect the seals from sharp tools and from the sharp edges of the surrounding components.

Any damage to the seals or the clamps will result in leakage. Leakage will allow water to leak into the front wheel drive shaft tripot joint and the front wheel drive shaft constant velocity joint. Damage will also allow grease to leak out of the front wheel drive shaft tripot joints and the front wheel drive shaft constant velocity joints.

Leakage may cause noisy front wheel drive axle operation and eventual failure of the internal components.

The clamps provide a leak proof connection for the front wheel drive shaft tripot joint and the front wheel drive shaft constant velocity joint at these locations:
^ The housing.
^ The front wheel drive shaft bar.

The thermoplastic material performs well under normal conditions and normal operation. However, the material is not strong enough to withstand these conditions:
^ Abusive handling.
^ Damage from sharp objects, such as tools or sharp edges of the surrounding vehicle components.

Front Wheel Drive Shaft Tripot Joint
The front wheel drive shaft tripot joint is made without an over-extension limitation retainer.

The joint is constructed as follows:
^ The left front wheel drive axle has a female spline. The female spline installs over a stub shaft that protrudes from the transaxle.
^ The right front wheel drive axle has a male spline. The right front wheel drive axle uses a barrel-type retaining ring in order to interlock with the transaxle gears.

Front Wheel Drive Shaft Constant Velocity Joint
The front wheel drive shaft constant velocity joint is of the Rzeppa joint design.

The shaft end, which mates with the knuckle/hub, has a helical spline. The helical spline ensures a tight, press-type fit.

This design prevents end play between the hub bearing and the front wheel drive axle.
Wheel Drive Shafts Description and Operation (M76) The rear wheel drive axles are flexible assemblies. The rear wheel drive axles consist of these components:
^ 2 wheel drive inner and outer shaft tripot joints.
^ A wheel drive shaft bar.

The wheel drive shaft bar connects the wheel drive shaft tripot joints. The wheel drive shaft tripot joints are completely flexible. Both wheel drive shaft tripot joints can move in and out.

Seals And Clamps
The rear wheel drive shaft tripot joint seals on the wheel drive axle are made of a thermoplastic material.

The clamps on the rear wheel drive axle seals are made of stainless steel.

The seals provide these functions:

^ Protection of the internal parts of the wheel drive shaft tripot joints.
The seals protect the grease from these sources of damage:
- Harmful atmospheric conditions, such as extreme temperatures or ozone gas.
- Foreign material, such as dirt or water.

^ Allows the angular and the axial movement of the rear wheel drive shaft tripot joints.

Important: Protect the seals from sharp tools and from the sharp edges of the surrounding components.

Any damage to the seals or the clamps will result in leakage. Leakage will allow water to leak into the rear wheel drive shaft tripot joints. Damage will also allow grease to leak out of the wheel drive shaft tripot joints.

Leakage and the loss to grease may cause noisy wheel drive shaft tripot operation and eventual failure of the internal components.

The clamps provide a leak proof connection for the wheel drive shaft tripot joints at these locations:
^ The tripot housing.
^ The wheel drive shaft bar.

The thermoplastic material performs well under normal conditions and normal operation. However, the material is not strong enough to withstand these conditions:
^ Abusive handling.
^ Damage from sharp objects, such as tools or sharp edges of the surrounding vehicle components.

Rear Wheel Drive Shaft Tripot Joints
The rear wheel drive shaft tripot joints are made without an over-extension limitation retainer. Care must be exercised when removing and installing the rear wheel drive shafts in order not to over-extend the tripot joints. Damage and tripot failure may result.

The joint is constructed as follows:
^ The wheel drive axle has a female spline. The female spline installs over an axle shaft that protrudes from the rear differential.
^ The wheel drive axle utilizes a barrel-type retaining ring in order to positively secure the inner tripot joint to the rear differential axle shaft.