Rear hub: functions and replacement instructions

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

The rear hub is designed to connect the movable wheel and the suspension element - the beam. The design of the hub can be compared to a small glass made of metal. A specially designed bearing is pressed into its inner part. A very simple device, but it can cause a lot of trouble to the motorist - when worn, the bearings begin to buzz a lot. And if you do not replace it in a timely manner, then the balls can completely jam, which will lead to wheel blocking and an abrupt stop of the car - when driving at high speed, this will lead to an accident.

Design Features

The rear hub 2108 is very different from the similar mechanism used in cars of the "classic" series - VAZ 2101-2107. The design of the rear suspension on front-wheel drive cars is quite simple. The axle shaft is mounted on the beam, it is somewhat similar to the steering knuckle mounted on the front axle. But there is one difference - this element can move in a vertical plane, but it will not work to rotate - the fasteners are rigid.

The hub itself isa small metal cylinder, hollow inside. A roller is pressed into it - a special bearing, with the help of which the wheel rotates on the axle shaft. Moreover, the outer diameter of this bearing is the same as the inner diameter of the hub. And the diameter of the inner race is the same as the outer half shaft. Consequently, the landing of the hub on the axle shaft is as tight as possible, there are no gaps. This can be understood by parsing the element just once.

Signs and causes of malfunctions

In the 2108 rear hub mechanism, it is the bearing that most often fails - this is the most vulnerable spot. But sometimes more specific breakdowns occur - cracks on the metal surface of the hub, destruction of the thread for the wheel bolts. In the second case, you can not completely change the hub, just cut a new thread. But this does not always help, it turns out to be easier to purchase and install a new one. Therefore, if, when tightening the bolts, they turn on the thread, you need to start repairing immediately, otherwise you may end up losing the wheel.

In the event that the bearing wears out, extraneous sounds appear - a strong hum that grows with speed. There may be several reasons:

1. Initially poor product quality.
2. Not enough grease inside the bearing.
3. Incorrect installation.
4. Resource exceeded.

In any case, it is required to replace the element. After the hum reaches its maximum, vibration will begin to appear - andthe stronger the wear, the greater the level of it will be.

What tools will be required

Before you change the rear hub or its bearing, make sure you have all the necessary tools. Without special pullers, it is unlikely that the bearing will be dismantled. If you plan to install a new hub assembly, then there will be no problems - it already has a new bearing, which is installed correctly.

But if you buy all the items separately, a puller is highly desirable. You need to have the following tools on hand:

1. Jack - preferably rolling type. And be sure to have solid foundations. If there are none, then wooden blocks can be used.
2. Balloon wrench for wheel bolts - usually a 19, 17 or hex head.
3. Pliers.
4. 30 socket or box wrench.
5. Section of a strong pipe.
6. Hammer, chisel, punch.
7. Wooden beam or bronze hammer.
8. Mounting spatula.
9. Any design wheel bearing puller.
10. A two-arm puller is required.

That's it, you'll also need a new bearing and hub nut. It is not recommended to reuse the old one.

Which bearings to buy?

The price of the hub assembly for VAZ-2108 cars and similar models is about 1200 rubles. The bearing will cost about 350-600 rubles (depending on the manufacturer and the greed of the seller). Not badthe results show some foreign manufacturers of bearings, but if you want quality and cheapness, then pay attention to domestic ones - Vologda or Samara. The first ones turn out to be much better, the service life is high. But you need to buy parts only from trusted sellers - there are a lot of Chinese consumer goods on the spare parts market, the quality of which leaves much to be desired.

Preparing to remove the hub

To dismantle the rear hub on the VAZ-2108 or any other car with front-wheel drive, preparatory work must be done:

1. Place the machine on a level surface. An inspection hole is not needed - all work is done without it.
2. Install under the front wheels shoes, turn on the first speed or reverse - this will provide maximum fixation of the machine. You can not squeeze the handbrake - because you will remove the rear drum.
3. Remove the protective cap to get to the hub nut.
4. Now you need to straighten the shoulders on the nut using a drift and a hammer.
5. Set the key to 30 and break the nut. Be sure to use a nozzle - a long pipe.
6. Only then can the wheel bolts be loosened.

Now you need to raise the repaired side of the machine and proceed to dismantle the hub.

How to remove the hub

In order to dismantle the rear hub, you need to perform the following manipulations:

1. Remove the brake drum by unscrewing the two guide pins. If athe drum does not lend itself, it is necessary to screw these guides into adjacent holes or carefully, using a spacer, tap it from behind.
2. Unscrew the hub nut completely, don't forget the washer underneath.
3. Using a three-legged puller, dismantle the hub. But you can use a simpler way - put the wheel on the back side and jerk it sharply.
4. If the inner bearing race remains on the axle shaft, it must be removed using a two-legged puller.

That's all, now you can put a new rear hub assembly. But if you need to replace only the bearing, you need to dismantle the old one and put a new one in its place.

Removing and installing bearing

To remove the bearing, you need:

1. Use special pliers to remove the circlips.
2. Remove the old bearing. To do this, you can use any method - with a puller, a hammer and a mandrel.
3. Thoroughly clean inside surfaces - if there are nicks, get rid of them.
4. Install the new bearing using a puller. Hitting with a hammer can damage the seal. It is advisable to warm up the rear hub, but not more than 50-60 degrees.
5. Install retaining rings - be sure to check that they are in the grooves.

After all these manipulations, assemble the entire assembly. After tightening the hub nut, bend the collars so that it does not unscrew.