Front wheel drives with equal angular velocity joints (CV joints) are used to transmit torque from the main gear installed in the gearbox to the front drive wheels at different wheel angles and suspension travels

The drives of the right and left front wheels are not interchangeable.

The wheel drive consists of inner and outer hinges of equal angular velocities connected by a shaft.

The drive shaft is made of forged steel bar.

Splines are made at the ends of the shaft, on which CV joints are installed.

External and internal drive joints have different designs.

Front wheel drives "A" - left, "B" - right: 1 - outer joint housing, 2 - large collar of the outer joint boot, 3 - outer joint boot, 4 - small collar of the outer joint boot, 5 - drive shaft of the left wheel, 6 - small clamp of the inner hinge cover, 7 - wheel drive inner hinge cover, 8 - large clamp of the wheel drive inner hinge cover, 9 - left wheel drive inner hinge housing, 10 - circlip, 11 - right wheel drive shaft, 12 - housing of the inner joint of the right wheel drive

The external drive joint provides the ability to transmit torque at various angles of rotation of the drive wheels.

Outer joint assembly: 1 - cage, 2 - cage, 3 - ball, 4 - body

The outer hinge consists of a body, a separator, a cage and eight balls, which are placed in the profiled grooves of the body and cage.

The separator constantly keeps the balls in the bisector plane between the body and the hinge cage and ensures uniform transmission of rotation from the cage to the body.

The hinge cage is mounted on the splines of the shaft and is fixed from longitudinal movement with a retaining ring.

The splined shank of the outer joint housing, at the end of which a thread is cut, is inserted into the front wheel hub and, when the nut is tightened, tightens the inner bearing rings.

The outer joints of the right and left front wheel drives are interchangeable.

Details of the left wheel drive inner joint: 1 - boot, 2 - spring thrust washer, 3 - spring, 4 - inner joint housing, 5 - circlip, 6 - three-stud

Internal hinge of the drive provides the possibility of angular movements of the suspension and compensates for the mutual movements of the suspension and the power unit by changing the length of the drive shaft.

The inner joints of the right and left wheel drives on a 4x4 vehicle are not interchangeable due to the different design of their bodies.

At the splined end of the drive shaft, on the side of the inner hinge, there is a hub with three spikes - a three-stud, on each of the spikes (trunnion) of which there is a bearing, the outer ring of which has a spherical surface.

The inner ring of the bearing is mounted on a stud with clearance and has the possibility of significant axial movement along the stud.

Three-stud bearing end positions

As a result of the operation of the front suspension, the bearings will move in the three longitudinal grooves of the hinge body.

At the same time, the spikes of the three-stud can take different positions relative to the bearings.

Clamped tenon end

Each end of the stud is crimped, as a result of which the bearing cannot be removed from the stud, so the assembly becomes non-separable.

Three-stud is fixed on the drive shaft with a retaining ring

A spring mounted inside the inner joint housing ensures that the joint housing is constantly pressed against the differential side gear.

The spline connection of the shank of the left wheel drive inner joint housing is fixedi in the side gear of the differential locking ring.

A rubber o-ring is installed between the splined hub of the right wheel drive inner joint housing and the transfer case shaft

The splined hub of the right wheel drive hinge housing is put on a snug fit on the splines of the transfer case through shaft.

The tightness of the hinges is an indispensable condition for their reliable operation.

The tightness of the outer and inner hinges is ensured by dirt-proof covers fixed to the shaft and the housing with disposable metal clamps.

Special lubricant for wheel drive joints is placed in the outer and inner joints before assembly.

It does not require replenishment or replacement of lubricant or any other maintenance of the wheel drives during the operation of the vehicle.

It is only necessary to monitor the condition of the protective covers of the hinges in the fastening of their clamps.

Distinctive features of the front wheel drives of a 4x2 car

Front wheel drive on a 4x2 car with automatic transmission: 1 - right wheel drive, 2 - left wheel drive

On a 4x2 vehicle, the right wheel drive inner joint housing rests on an intermediate support, which also holds the joint housing from axial displacement.

The support bearing of the intermediate support, pressed onto the shank of the hinge housing, is installed in the bracket of the engine block and is closed with a cover.

The cover is installed on the axis of the bracket and is attached to it with a bolt.

The splined end of the shank of the left wheel drive inner joint housing is inserted into the hole of the differential side gear.

Front wheel drives on a 4x4 car: 1 - right wheel drive, 2 - left wheel drive

On a 4x2 vehicle, the outer drive joints are interchangeable, while the inner ones are non-interchangeable.

Operations for repairing the front wheel drives of a 4x2 car are the same as the corresponding operations for the drives of a 4x4 car.

Possible malfunctions of the front wheel drives

Cause (Remedy)

Vibration when driving:

- Strong wear of the outer joint of the wheel drive

Replace worn hinge

- Deformation of the wheel drive shaft

Replace the wheel drive shaft

- Wear of the rollers of the inner joint of the wheel drive

Replace inner hinge

- Loosening the hub nut

Tighten or replace the nut

Moving the car to the side:

- Wear or damage to the inner joint cage

Replace hinge

- Wear or damage to the outer hinge

Replace hinge

- Damage or deformation of the wheel drive shaft

Replace shaft

- Loosening the hub nut

Tighten or replace the nut

Grease leaking out of hinge:

- Wear or rupture of the protective cover of the outer or inner hinge

Inspect the hinge, if there is play, replace the damaged cover and grease

- Insufficient tightening of clamps

Replace and securely tighten clamps

Noise, knock from the front wheel when the car is moving

- Damage or deformation of the wheel drive shaft

Replace shaft

- Runout of the front wheel drive shaft

Replace shaft

- Damage to the bearing of the intermediate support of the drive of the right front wheel of a front-wheel drive vehicle

Replace bearing or drive assembly

- Wear of the rollers of the inner joint of the wheel drive

Replace inner hinge

- Loosening the hub nut

Replace or replace the nut

Knock when car turns:

- Strong wear of the outer joint of the wheel drive

Replace hinge