The running system performs many functions, the main of which is ensuring the controllability of the car. To make the machine maneuverable and safe, it is equipped with a special steering knuckle and a hub between the axles. In order for them to be as reliable as possible, they include two bearings each. Both parts may differ in size and cost, but their design remains unchanged. Both the front and back are tapered. Although some motorists claim that the rear hub bearing is easier to operate than the front one. To finally find out the answer to this question, in today's article we will consider all the features of this part.
First, let's look at the design of this element. As we have already found out, the rear hub bearing has a conical shape. So - it is attached to the axis with a special thrust nut or washer. The more this part is tightened, the tighter the rollers will be pressed. Thanks to this, the possibility of backlash of the mechanism can be excluded.
So why is a rear hub bearing easier to operate?
The design of the front and rear parts are very similar to each other, but there are some differences. The fact is that the rear hub bearing does not have therefore it is easier to operate. Now several types of these parts are installed on cars:
- deep groove ball bearings (most often for machines with dependent suspension);
- conical (for independent).
The first mechanisms differ from the second ones in that they do not have the ability to adjust the degree of pressing the rollers to the clips. They are much cheaper, and you can buy them absolutely in any town.
Why does a rear wheel bearing fail?
It often happens that this part fails due to road dust that has got into its body. This can be due to leaking oil, but most often it happens due to water getting onto the hub. Well, no one is safe from hitting a puddle. So it turns out that it’s best to have a couple more such details in your trunk so that at one fine moment you don’t have to go home on a tow truck. But having a set of new parts with you is half the battle. You also need to know how to change the rear wheel bearing. Therefore, below we will give a small instruction on the removal and installation of this part.
rear wheel - step by step process
First, remove the protective cap of the hub fastening nut and lower the tightening of the wheel bolts and the mechanism itself. After that, we take a jack and raise the car by 5-10 centimeters. In this case, do not forget about additional supports. Next, turn on the first gear and put the substrate under the front wheels. Then remove the wheel and pads. Next, using a puller, we dismantle the hub from the trunnion and the inner race of the bearing. The next step is to remove the retaining ring and then the bearing itself. All mechanisms are thoroughly washed, and a new part is pressed into the hub. The rear wheel bearing is installed in the reverse order.
During the movement of the car, a specific hum may occur, changing the tone to low at low speeds or noise with a possible rattle at high speed. Such troubles can create a hub bearing. The performance characteristics laid down by the manufacturer should allow the driver not to think about this wheel element for a long time.
However, road realities make their own correction. The primary reason a rear hub bearing needs to be replaced is not physical wear, but mechanical deformation. The driver does not have time to notice all the holes on the road, and for the failure of vulnerable parts, it is enough to get into only one of them.
A constant rumble from the rear wheels should alert the driver, and it is necessary to stop in the nearest place and check the bearing's performance. The term of its high-quality work is usually about 100 thousand kilometers. While approaching such a parameter, you need to start diagnosing their condition.
For this to work, you will need to do the following:
- required lock the wheels located diagonally to the ones being diagnosed, because you need to check on both sides, since in the cabin it is not always clear where the noise is coming from;
- jacked up spin the wheel as much as possible hands until a familiar rumble is heard, usually a characteristic problematic sound is noticeable almost immediately, because a high-quality bearing works without rattle, crunch and buzz;
- on a doubtful wheel, it is worth checking the transverse play using a simple procedure, holding the wheel, you need to shake it away from you and towards you, and the presence of a noticeable movement is an indication for replacing the bearing.
You need to know that most car dealerships offer a hub assembly with a bearing, but if the bore diameter has no wear or deformation, then you can not change the hub, but buy a separate repair bearing.
Replacement procedure
Before changing the rear wheel bearing, we block the car with the help of wheel chocks. We loosen the fasteners on the diagnosed wheel. Also, having got rid of the central cap, we release the central nut by 1-2 turns. Now you can jack up this side.
We install safety racks under the body and remove the wheel. The seat of the brake drum can be filled with WD-40 to facilitate dismantling. In some cases, brake fluid or diesel fuel is used. Before unscrewing the guide bolts, they are usually tapped with a copper hammer so that the “sticky” thread “succumbs”.
Dismantle the brake drum. In problematic cases, a special remover is used for such an operation, and for easier situations, bolts are screwed into the thread intended for them, with their help an interference is created for removal.
Step 1. Remove the cap 
Step 2. Unscrew the nut with a puller 
Step 3. Remove the hub with a puller 
Step 4. We take out the ring and prepare the bearing 
Step 5. Press the bearing with a puller 
Step 6. Mount the hub back 
Step 7. Rolling the Nut
Remove the central nut and stretch the entire hub along the axis. Sometimes a bearing race remains on the shaft, then using a puller or chisel, dismantle it separately after the hub. We carry out the operation so as not to damage the landing surface.
We inspect the axle to detect rotation of the bearing cage. If there are such traces (the presence of grooves on the landing diameter), then the hub will also have to be changed.
You need to know that the formation of serifs with a chisel or a breakdown on a worn surface for a more rigid fit of the bearing race is strictly unacceptable! It is necessary to change the worn hub completely in such a situation!
The current replacement of the rear wheel bearing can be carried out with concomitant diagnostics of other elements. It is worth simultaneously checking the brake cylinder for leaks, and the brake pads are monitored for wear.
Using a removable tool, we take out the retaining ring, and if necessary, fill in special cleaning fluid under it to make the bearing easier to press out. It is customary to use one of three popular methods for dismantling the outer race from the hub:
- using a hydraulic press, which is not found in every garage;
- reusable puller, its cost is affordable, and you can use the unit in the future;
- with a hammer or sledgehammers 2-3 kg, for this method a special spacer of the appropriate diameter is required.
We install the hub on a hard surface and apply a couple of blows on the prepared mandrel with a hammer. This is done carefully so as not to damage the seating surface with a mandrel or other parts with a heavy hammer.
The surface freed from the clip can be cleaned with fine sandpaper from possible corrosion spots and then lubricated with oil (working off is allowed). It will facilitate the installation of a new bearing, which must first be assembled using two washers and a bolt. The outer diameter of the washers should be 2-3 mm smaller than the bearing diameter.
Lubricants can be added to the double row separator before assembly. With the help of a hammer, preferably with a copper or bronze ending, lightly tap on opposite sides to "plant" the bearing.
You need to know that bearings are made from high-alloy steel, which can crumble under strong dynamic loads (sharp impacts), so it is recommended to use a “soft” copper or bronze spacer so as not to damage the cages.
If at the initial stage the entry turns out to be tight, then there is probably a bias, so it is worth leveling it with light blows, and not applying unnecessary force. When the new clip comes in half, the old one can be used as a spacer. We continue until the groove for the retaining ring appears. We fix the bearing with a ring.
Hub mounting
We get rid of the tightening device from the bolt and two washers. Now you can return the hub to its place. Be sure to install a new central nut, having previously lubricated the thread with "lithol" or other lubricant.
We install the brake drum on the fasteners. We put the wheel and fix it with fixing bolts. We turn the wheel "by hand" and listen to extraneous noise. The absence of a hum or rattle, as well as free rotation, indicates the correct assembly.
We lower the wheel with a jack, and only after that we carry out the final tightening of the central nut. It is recommended to use a torque wrench for this operation. The preload value should be close to 20 kg/m. This value is quite large, so without a special key, you will need to increase the key length. Now the hook can be centered and the mounting bolts on the wheel can be tightened to the required torque.
Unfortunately, sometimes our cars break down and need to be repaired, it is necessary to change various parts, optics, and in some cases, the rear hub bearing needs to be replaced, although, as statistics show, this happens quite rarely.
How to recognize problems in the hub?
The fact is that the hub is the most important element of any rotating mechanism, including an automobile wheel. It is a central part of rotating parts with a hole for the possibility of fitting it onto an axle or shaft. Thus, its main task is to provide rotational motion. In order to prevent free rotation on the axle, rolling bearings or special plugs are pressed into the hub hole. In addition, it is thanks to the bearings that the hub, as well as the wheel, can rotate.
It is quite easy to notice that it is urgent to replace the hub bearing, in this case there is a characteristic knock in the rear lower part of the body, most often, it intensifies when driving on rough roads or when hitting pits, as well as mounds. While driving on a relatively smooth road surface, a hum may occur. In addition, the brake drum is very hot.
Checking if the rear wheel bearing needs to be replaced
First of all, the cause of such a breakdown is bad uneven roads, especially since in some cases our road surface can hardly be called a road at all. The second reason why the bearing may become unusable is the poor-quality material from which it was made. the rear wheel is not a very complicated process, so it can be done quite easily on your own at home.
However, before proceeding directly to the actions, you should find out whether it really is the case. To do this, you need to hang out the wheel from which the rumble is heard, and, swinging it with your hands, check the play. If, during the implementation of these actions, the backlash is detected, and at the same time there are deaf knocks, then it is impossible to delay the replacement. A bearing falling apart along the road will cause damage to other parts of the hub system.
The key to fast and high-quality work is the right tool and high-quality materials, in this case the bearing. Therefore, do not try to save on it, purchase options only from good manufacturers, because the service life largely depends on this.
Replacing the rear hub bearing - your steps step by step
From the tool you will need a screwdriver, a jack, a wheel wrench, lithol, a hub nut puller, sometimes chisels and a pry bar. Next, having prepared everything you need, we proceed as follows. We put the car in first gear, having previously placed “boots” under the front wheels. We raise the car with a jack and dismantle the desired wheel. Having unscrewed the guide pins, you need to remove the brake drum, most often it is knocked down. Now the hub nut is unscrewed with a special puller and the hub itself is knocked off the trunnion. It must come off with the bearing ring, otherwise it must be removed with a pry bar and a chisel.
In order to press the bearing itself, it is necessary to remove the retaining ring with special pliers and knock off the metal boot. Next, you need to lubricate the seat and use a special puller to press the new bearings back. At the same time, keep in mind that it is highly undesirable to score them.. Now back and retaining ring. By hitting the inner ring of the bearing, we put the hub back on the trunnion. Next, you need to tighten the trunnion and hush up its sides as best as possible. The process is almost completed, the pads, the brake drum and, of course, the wheel are being installed in their original places.
A failed rear wheel bearing indicates a permanent problem, often. It comes from behind and does not disappear when driving in neutral. As bearing wear increases, this sound can increase more and more. The rear wheel bearing needs to be replaced.
This work can be done most quickly with the help of special tools (pullers). If they are not, then to achieve the goal, improvised materials should be used. Consider carrying out a bearing replacement with this slope.
Checking the rear wheel hub bearing
We hang the wheel on the bearing of which there are suspicions. We rotate it by hand. A wheel with a good bearing spins almost silently. A defective bearing gives itself out with noise and the sound "as if the balls are rolling in the bearing." The degree of noise and rolling depends on the degree of wear of the wheel bearing itself. For comparison, you can hang a wheel with a serviceable bearing and listen to what sound it rotates.
Required Tools
- An elongated head by 30 with a long collar, or a curved ring wrench of the same diameter (or a similar socket wrench, etc.)
For loosening the wheel nut.
— Thin chisel, center punch
For bending the jammed edge of the hub nut.
- Three-legged puller(not required)
To remove the hub from the wheel axle.
- Two-legged puller, or a special semicircular(not required)
For removing the bearing inner race from the wheel axle.
- Puller - pliers
For removing and installing retaining ring
- Puller for pressing the bearing out of the hub / pressing the bearing into the hub(not required)
- Open-end or any other key for 12(11, 8, 7 - depending on the type of pin)
For loosening the guide pins holding the brake drum.
— Key for 13 (14)
For loosening the parking brake adjusting nut.
rear wheel bearing for VAZ 2108, 2109, 21099 with nut Preparatory work
Work is best done in a pit (inspection ditch), as it is more convenient. But if there is no hole, you can do without it.
- fixing the car, putting it on a flat area, in first gear, placing wheel chocks under the wheels.
- Under the bottom of the car, loosen the handbrake tightening nut.
If the car is not installed on a pit (inspection ditch), then to perform this operation, you will have to jack up one of the wheels, put a safety stop under the car and get to this very nut lying down.
The procedure for replacing the rear wheel hub bearing on VAZ 2108, 2109, 21099 vehicles and their modifications
- Remove the protective cap on the wheel hub
- Remove the dent on the side of the hub nut
Using a thin chisel or core and a hammer, straighten the jammed edge. For greater clarity, the wheel in the image has already been removed.
dent on the edge of the wheel nut - Loosen the hub nut
To do this, use a 30 head with a long knob (or a special key) to unscrew the nut. You may have to apply considerable force and lengthen the key handle with a metal pipe, as it may boil or rust over time. Also, to prevent the wheel from spinning, in the passenger compartment, the assistant can press the brake pedal.
loosen the rear wheel hub nut - Remove the wheel
We loosen the rear wheel mounting bolts, jack it up, substitute the safety stop, unscrew the bolts, remove the wheel.
- Remove the brake drum
With a key of 12 (11, 10, 8, 7 - there may be a different size of the pin), we unscrew the two guide pins that secure the brake drum. If they do not want to turn away, lightly tap them with a hammer.
unscrewing the two guide pins of the wheel disc on the brake drum Since we have already loosened the parking brake, the brake drum should be removed without much difficulty. Hands rotate it left and right and at the same time pull it towards you. If it goes badly, we tap the drum in a circle from behind with a rubber mallet. This should help.
brake drum removed - Finally unscrew the hub nut
We remove it and the washer under it.
- Remove the rear wheel hub with bearing
We install a three-legged puller on the hub and, turning its nut, pull it off the wheel axle.
removal of the rear wheel hub of VAZ 2108, 2109, 21099 cars using a puller If there is no puller, we take the wheel, turn it over with its back side towards us and fasten it to the hub with wheel bolts. We wrap the bolts not completely, but several turns (it is desirable, of course, to use elongated bolts, but if they are not available, you can use regular ones). We will use the wheel as a reverse impact hammer. With a sharp movement we move it towards ourselves. If it was not possible to remove the hub from the axle at once, we perform this operation several times.
- Remove the bearing inner race from the wheel axle
You can use a two-legged or semi-circular puller, or you can simply put a large chisel behind the ring and hit it with a hammer. The ring will move along the axis, then it can be pry off with a mounting spatula or a large screwdriver and finally removed. If after working with a chisel there are nicks on the axis, we clean them with a small file.
Removing the rear wheel bearing inner race - Remove the retaining ring that secures the bearing in the hub
We use a pliers for this. If it is not, remove the retaining ring with a screwdriver.
Removing the retaining ring of the bearing in the hub using a puller - Remove the bearing from the hub
Using a special puller, we squeeze it out of the hub housing. If there is no puller, we knock it out with a piece of pipe of a suitable diameter. The diameter of the pipe must be equal to the diameter of the inner ring of the bearing. We strike at him.
knocking the old bearing out of the hub - Clean and lightly lubricate the inside of the hub
- Press the new bearing into the hub
We do this with a puller or vise, or simply hammer it in there using a wooden spacer and hammering in a circle. At the final stage of this driving, you can use the old bearing as a spacer.
driving a new bearing into the hub - We install a retaining ring in the groove on the hub
You can use a pliers for this, you can just use a screwdriver.
rear wheel bearing circlip - Install the hub with the inserted bearing on the axle
mounting the hub onto the rear wheel axle - We put on the washer and the hub nut.
install washer and hub nut - Tightening the nut, press the hub all the way onto the axle.
tighten the nut - Replace brake drum and wheel
- Finally tighten the hub nut with a torque of 186.3-225.6 N.m (19-23 kgf.m)
If there is no special key to determine the tightening torque, then we remember with what effort the nut was unscrewed, with approximately the same force it must be tightened.
The rear hub bearing is a very important element of the rear wheel rotation mechanism. The main task of the bearing is to ensure that it smoothly ensures the rotation of the wheel. In this article, we will look at how to replace the rear hub bearing with our own hands, so as not to go to a service station, where they will take normal money for work.
When an unpleasant knock appears in the area of \u200b\u200bthe rear wheels, mainly on bumps or small pits, and on a flat road a characteristic hum is a message to the motorist that the rear hub bearing is faulty and needs to be replaced. I do not recommend delaying the repair, as this breakdown can pull the rest of the components and assemblies of the car.
Video. Do-it-yourself rear wheel bearing adjustment
Note that in the previous article we considered its work and do-it-yourself replacement. Due to improper idle adjustment, the car has problems with increased fuel consumption, so I recommend paying attention to this article.
How to determine if the rear wheel bearing needs to be replaced?
The main cause of rear wheel bearing failures is our most beloved domestic roads, which are simply in a terrible state. Road bumps and pits simply knock out the bearing, it quickly goes into disrepair. Another reason, quite popular in recent years, is the poor quality material from which the bearing is made. Self-replacing the rear wheel hub bearing on a car is a fairly simple repair that can be done in a garage.
Video. Do-it-yourself installation of rear wheel hub bearings
How to determine if the problem is in the rear hub bearing? Everything is very simple, you need to raise with a jack the side where the knock or rumble is pronounced, take the wheel with your hands and swing it. Thus, we will check the wheel play and if it is found, an immediate replacement is required. A bad bearing can damage the rest of the system in the hub.
