What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car
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What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car

The suspension in the car is needed not only to increase ride comfort, but also to preserve important parts and assemblies that would quickly crumble with constant shaking. The car's suspension takes over and dampens all the bumps on the road. However, in order for the shocks to be minimally transmitted to the body, dampers are needed.

For this purpose, support bearings are provided in the machine design. We will figure out why they are needed, how to determine that they are faulty, and also how to replace them.

What is a thrust bearing

This part refers to the element installed at the top of the damper strut. A rod is attached to the part through the central hole, and a spring rests on the plate placed in the bowl.

What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car

This part has the form of a bearing with a damping element that provides additional damping of vibrations that occur during suspension operation. It is installed on front-wheel drive cars, and then only if the shock absorber is attached to the knuckle of the steering wheel. For this reason, this assembly implies the use of bearings of a special configuration, otherwise the body cup would quickly wipe off and the seat would break.

What is a support bearing for?

What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car

This suspension part has several functions:

  • Support. At the top of the rack, you need to rest against the body so that the body of the car has a solid support and is connected to the chassis;
  • Damping element. If the shock absorber rod was rigidly fixed to the body, the suspension operation would be clearly audible in the cabin. For this reason, the body and stem attachment must be separated. For this purpose, a rubber insert is included in the support structure;
  • Rotate while turning the steering wheel. Some vehicles are equipped with a stably fixed rack. Even when turning, it remains stationary. In this case, the shock absorber rod simply rests against the sleeve with the damper. In other cases, when the shock absorber is attached to the steering knuckle of the car's undercarriage, a bearing must be present in the support device. It provides a smooth stroke during rotation.

Устройство

The device of the simplest modification of the OP consists of:

  • Rather a plate. It most often contains an attachment to the body (these can be threaded studs or just holes for bolts);
  • Bottom plate. Another support element, the purpose of which is to rigidly fix the bearing in place and prevent the outer sleeve from moving under load;
  • Bearing. There are several types of them. Basically, it is pressed into the body between the plates so that it sits firmly and has no backlash.
What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car

Different modifications of the upper supports are needed, since each car has its own body and the principle of mounting the suspension.

The strut support differs from conventional bearings in that it contains rollers rather than balls. Thanks to this, the device can withstand large multidirectional loads.

Types of support bearings

The existence of different types of support bearings is explained by the evolution of the mount and the increase in the efficiency of the element. In total, there are four types of OP:

  1. Version with inner pressure ring. In it, the mounting holes are made immediately in this ring;
  2. Model with detachable outer ring. According to mechanics, such a support is most effective. Its design is as strong as possible and can withstand heavy loads. The outer ring is attached to the body;
  3. A model that is fundamentally different from the previous one - the inner ring is attached to the body, and the outer one remains free;
  4. Modification with a single split ring. In this case, the design ensures maximum accuracy of the inner ring rotation together with the required structural rigidity.
What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car

Whatever the modification of the opornik, its main enemy is moisture, as well as grains of sand. To provide maximum protection, manufacturers provide various kinds of anthers, but they protect the node only from the top, and the lower part still remains vulnerable.

Signs of a failed thrust bearing

The following factors indicate a breakdown of the OP:

  • Knocks from the front of the car when the driver turns the steering wheel. Sometimes the beat is transmitted to the steering wheel;
  • Reduced vehicle handling;
  • The feeling when turning the steering wheel has changed;
  • The car has lost stability - even on straight sections of the road, the car drives in one direction or the other.
What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car

It should be borne in mind that such noises during a bearing breakdown are not manifested in all cases. An example of this is OP VAZ 2110. In this car, the inner bearing sleeve is a sleeve for the rod.

When a part wears out, play appears in it. Because of this, the wheel alignment is lost in the car. Even when there are no other problems with tires, wheel balancing and steering, the car needs constant steering on the straight sections of the road.

In some machine models, the strut support has an additional rubber bushing, which, when worn, provides a knock in a faulty bearing.

What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car

The causes of breakage and premature wear of this part are:

  • Natural wear and tear of elements experiencing constant multidirectional loads;
  • Bump rides;
  • Water and sand;
  • The car often falls into deep holes (at high speed, the maximum load on the suspension is in such cases);
  • Poor part quality;
  • Poor support with nuts.

How to diagnose a malfunction?

The most effective way to determine that the malfunction is in the support is to remove the part and look at its condition. Besides this method, there are two others:

  1. Two people - one swings the car in the longitudinal and transverse directions, and the other conducts a visual inspection of the cup. This method detects backlash. Turning the steering wheel will also help find a little free play in the bearing in the housing;
  2. The second option will help to reveal significant backlash. When performing this procedure, there is no need to resort to outside help. It is enough to swing the car yourself for the support cup. A strong backlash will immediately make itself felt.
What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car

When performing diagnostics, it should be remembered that the work should be done without hanging the wheels and on a level car.

Support bearing lubrication

In order for the bearing to work for its entire service life or a little more, some craftsmen recommend periodically lubricating the part. Also, the lubrication reduces the negative impact on the elements at high loads.

What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car

Here's what you can use to lubricate the OP:

  • Grease for CV joints;
  • Liqui Moly LM47 is a product based on molybdenum disulfide. The disadvantage of this substance is the loss of properties upon contact with moisture, therefore, such a grease is best used in bearings equipped with protective caps;
  • Litol is the most effective of the budgetary funds;
  • Varieties of Chevron greases. They are multipurpose and are therefore suitable for supporting journal bearings.

When deciding which lubricant to use, it is important to remember that all bearings still have a working life, and therefore, sooner or later, the part must be changed. The manufacturer sets its own spacing, so you should adhere to the recommendations for individual elements.

Replacing the support bearing

Before considering the step-by-step instructions for replacing a part, it is worth noting that these are only general recommendations. Repair of an individual car can have its own subtleties, as the master learns from technical literature.

What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car

The support frame changes in the following sequence:

  • The machine is jacked up;
  • Wheels are unscrewed;
  • The shock absorber strut is dismantled (in each case, the car has its own mount, so you need to adhere to the principle established by the manufacturer);
  • Using a puller, the spring is compressed until it comes out of the seat;
  • The nut is unscrewed from the stem. It should be borne in mind that when unscrewing it, the stem will turn, so you need to use a special key that clamps this rod;
  • The old bearing has been released. Now you can install a new one and screw the nut back;
  • Check if the spring is correctly positioned in the support;
  • Spring puller is smoothly removed;
  • The rack is installed back on the machine;
  • The wheels spin.

Which support bearing to choose

Finally, a short overview of the brands. In most modern modifications, the bearing is not sold separately - more often it is already pressed into the support housing. Choosing from the list below, it is worth considering that not every manufacturer makes this kind of spare parts for all machine models.

What is a thrust bearing. Let's disassemble the front strut (shock absorber) in the car

Popular OP manufacturers include the following:

  • Chinese brands - SM and Rytson. The products of these manufacturers belong to the options with a "golden mean" between price and quality;
  • The French manufacturer SNR produces parts for many well-known auto brands;
  • One of the most popular and well-known worldwide manufacturers of auto parts - SKF;
  • More reliable products - from the German manufacturer FAG;
  • For connoisseurs of Japanese quality, you can look for parts made by Koyo, NSK or NTN.

For a budget car, it makes no sense to purchase the most expensive spare part, because due to the simpler design of the chassis and suspension, more load will be placed on the spare part. However, it is also not recommended to buy the cheapest option, because, given the quality of most roads, the bearing will have to be changed much more often.

We offer a short video about replacing the support bearing with your own hands:

KNOCK IN FRONT SUSPENSION. Support bearing, or Strut support. # car repair "Garage No. 6".

Questions and answers:

How to identify a defective shock absorber support? First of all, this will be heard by the characteristic knocks while the car is moving (it has a direct connection with the body) due to the slightest backlash.

How does a shock absorber support bearing work? This bearing allows the shock absorber to rotate freely in the support. The design of the support bearing is mounted in the "glass" of the car body.

How to change the bearing in the strut support? The car is hung out, the steering rod and the swing arm are released, the steering knuckle is partially disassembled, the lower part of the rack is released. The spring is compressed, the stem nut is twisted and the fastening bolts are unscrewed. Everything is assembled in the reverse order.

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