Description
1. Torque is transmitted to the rear axle through a semi-balanced hypoid final drive (the gear axis is located below the driven wheel axis). When turning the car, due to the presence of a differential, it is ensured that when the car enters a turn, the inner wheel, which rotates slower than the outer one, rotates its side gear more slowly than its outer wheel. The pinions roll on the side gear, which rotates more slowly, allowing the outer wheel and its side gear to rotate at a higher speed.
2. As an option, the vehicle can be equipped with a rear differential that locks when the wheels slip. The differential operates as usual until the torque on one of the wheels decreases. A locking differential is similar in design to a conventional differential, but has a feature - on each side of the side gears there are limited friction clutches that prevent one of the wheels from stopping while the other wheel is slipping; the torque between the wheels occurs due to friction between the side gears and couplings having a splined fit on the axle shafts.
3. All-wheel drive models have a fully independent front axle suspension. The design provides for a differential and two axle shafts. Each axle shaft has an internal and external constant velocity joint (CV joint). Since the differential is shifted to the left (removed from the engine and combined with the transfer case), the left wheel is located closer to it than the right one. Therefore, a longer axle shaft is installed on the right side, which passes through the engine sump channel. On vehicles with controlled all-wheel drive (S4WD) turning on and off the right drive shaft is carried out through the fork and bushing. This ensures that both axle shafts rotate at different angular speeds when the car turns. On vehicles with automatic all-wheel drive, a differential of a similar design is used; the difference is that with an automatic drive, the design does not include a fork and bushing for the switching mechanism.
Inspection
4. It is often possible to mistakenly assume that an axle has failed, while problems have arisen in another component of the vehicle. Before making a decision about the failure of the bridge, carry out a series of checks, during which the presence of malfunctions of other elements will be excluded.
5. When diagnosing, the following sources of characteristic noise should be taken into account:
- A) Road noise is often mistaken for bridge noise. Drive on different road surfaces and determine the source of the noise. The frequency and volume of noise produced by the road surface does not change depending on the load on the vehicle's transmission.
- b) Sometimes the noise coming from the tires when the car is moving is mistaken for noise that could be made by an axle. Tires that are worn to the limit or have low internal pressure often make noise during operation and cause increased vehicle vibration when driving. Bridge noise varies under different driving conditions (coasting, acceleration, etc.), and tire noise remains at the same level.
- With) Vibration and various noises emitted by the engine or gearbox and transmitted to the axle via the driveline can serve as an erroneous basis for determining its failure. Note the engine speed at the highest noise level. Stop the car, move the selector lever to neutral and accelerate the engine to the marked speed. If the noise remains at the same level, a bridge malfunction should be ruled out as the cause of the noise.
6. It is not advisable to repair the differential yourself, since this requires the use of special equipment. This chapter describes the procedures for removing and installing axle shafts, replacing their seals and bearings, as well as the procedure for removing the entire differential for subsequent repairs at an auto repair organization or replacement.