The rear axle is equipped with an automatic differential lock. The locking mechanism is controlled by a centrifugal regulator. This device is activated automatically if one of the drive wheels spins and the vehicle speed does not exceed 40 km/h. If the vehicle is traveling at a higher speed and both wheels are spinning at the same speed, the differential operates the same as a conventional differential.
Limited slip differentials (limited slip) include couplings that are designed to connect each of the axle shafts to the differential housing. The clutches can be engaged either by spring action or by pressure generated by the torque generated by the rotation of the axles. When driving on dry roads, the clutch action prevails and each wheel rotates at the required speed. If slippage occurs at any wheel, the clutches transmit the amount of power to the wheel that creates the greatest traction. Due to the presence of limited slip differential clutches, a special lubricant is required.
The main gear has a specific gear ratio. This value is usually calculated based on the ratio of the number of teeth on the ring gear and the pinion gear. On your car, the ring gear has 37 teeth, and the pinion gear has 15. Therefore, the gear ratio is 2.47.
The main transmission is carried out by a hypoid transmission with a pinion located below the ring gear.
On vehicles with independent suspension, the axle shafts are bolted to the differential. Each axle shaft has a constant velocity joint (CV joint) at one end, which completely transmits movement when the car bounces.
Rear axle diagnostics
Quite often, a fault is suspected in the rear axle area, although, in fact, it is located somewhere else. For this reason, a thorough inspection is necessary before deciding that there is a fault with the rear axle.
Based on the noises listed below, diagnostic procedures can be performed on the rear axle.
Noise from mechanical failures is often confused with road noise. By driving on different road surfaces, you can determine whether the noise is actually caused by the road surface. The noise from the road surface will be the same whether the car is moving under load or when coasting.
Sometimes noise from mechanical problems is confused with tire noise. Tires that are worn or have low air pressure vibrate and make especially loud noise. Tire noise remains approximately the same under different driving conditions, whereas noise from a faulty rear axle will change when coasting, accelerating, etc.
Noise from the rear axle can be confused with noise from the engine and transmission, since the rear axle is located transversely to the driveshaft. To isolate noise from the engine and transmission, it is necessary to record the rotation speed (speed) engine at which the noise is most pronounced. Stop the vehicle, put the transmission in neutral and accelerate the engine to the RPM value that was recorded earlier. If the noise remains the same, it means that the source is not the rear axle.
If the nature of the noise changes, then it is likely that the source of the noise is the final drive gears, or the bearings of the pinion gear or differential.
With the vehicle stationary and braked, listen to the engine running in various modes to eliminate noises caused by its operation.
Raise the car and place it on stands. Start the engine, engage the gear and the "USK" mode (all-wheel drive).
A car enthusiast cannot repair the rear axle on his own, as this requires the use of special tools and precise measuring equipment.