Do the correct diagnostics. Self-diagnosis of the rear and front suspension

The appearance of a knock in the front suspension of a vehicle causes unpleasant thoughts in the driver. Some car owners may even start to panic. But this should not be done. The suspension of the car is designed for severe operating conditions and has a fairly large margin of safety. If third-party sounds have just appeared, then you should not immediately run headlong to a service station. The initial diagnosis of the front suspension can be carried out independently and even eliminate some of the defects with your own hands.

Causes of knocking in the front suspension

The suspension of a car is a set of mechanisms that connect the car body with the road. Therefore, the appearance of a knock or creak is primarily associated with the condition of the road surface. There are many surprises waiting for any driver on highways and city roads. These can be potholes, pits filled with water, bumps, a recently installed speed bump, poor road lighting at night.

The appearance of a knock or creak is primarily associated with the condition of the road surface.

The second reason for the appearance of noise and knocking is mechanical damage to the elements and parts of the front suspension if any maneuver is performed incorrectly. First of all, this is emergency braking before a defect on the road, which was noticed too late. Usually this behavior is characteristic of novice drivers. They continue to press the brake pedal while the wheel hits the pothole. Mechanisms and so work in extreme mode. The load experienced by the suspension strut increases several times during braking. In this state, the suspension suffers from impact much more.

The second reason is mechanical damage to the elements and parts of the front suspension if any maneuver is performed incorrectly.

The third reason is physical aging or factory defects in parts. This is especially true for various rubber anthers, bushings, silent blocks. These parts are in an aggressive external environment and constantly experience great physical stress during movement.

The fourth reason is not frequent, but do not forget about it. The appearance of extraneous noise from the front suspension may be due to poor-quality car repairs. It happens that an unscrupulous master, when replacing or repairing a suspension, forgot to fasten or tighten something as expected, or vice versa, overdid it and overtightened the nuts.

Self-diagnosis of the front suspension

If the driver hears a knock or creak while driving, then the suspension itself has already “diagnosed” and sends a signal to the car owner. This warning should be responded to as quickly as possible, otherwise the untimely repair of one part will entail other problems. After all, the suspension is a set of interacting mechanisms and parts.

To carry out diagnostics on your own, it is better to drive the car onto a flyover or inspection hole. Inspection of the front suspension is recommended to be carried out with protective gloves and with a small mount. And after self-diagnosis, make a conclusion: go to the service or not. Some causes of third-party knocking or creaking can be eliminated on your own by tightening the threaded connections or replacing the rubber bushings.

So, let's start diagnosing. First, you should inspect all the rubber anthers that protect the ball joints, steering tips and CV joints (grenades). If they are damaged, dust and dirt can get inside. This leads to breakage of the ball joint. Ball joints are diagnosed using a mount, loading them. So check for backlash. If everything is correct, then it should not be.

Ball joints are diagnosed using a mount, loading them

Suspension struts, which are also elements of the car's suspension, should be inspected for leaks. If there are, then you need to change the racks. The old method of testing shock absorbers by rocking the car body has not worked for a long time. The only way to really check the rack is to remove it.

The next stage of diagnostics includes an inspection of the silent blocks in the front levers. As you know, these parts consist of metal bushings and rubber inserts. Perhaps they have ruptures in the rubber part or it is badly cracked. If these defects are present, the silent block should be replaced.

Often, a knock appears due to a malfunction in the disc brakes. To check them thoroughly, you need to remove the wheel. Perhaps, due to the poor quality of the pads, the friction lining peeled off and it caused third-party noise. Calipers can knock. This is due to the wear of the guides.

Often a knock occurs due to a malfunction in the disc brakes.

Many causes of extraneous knocking or creaking in the front suspension can be eliminated with your own hands. For example, it will not be difficult to replace the rubber bushings of the stabilizer. They are attached to the body with a bracket and one or two bolts. But if you have doubts about your abilities, then it is better to contact the specialists at the service station. Remember, a good suspension is a guarantee of safety for the driver and passengers. Yes, and driving a car without extraneous sound is much more comfortable.

Any motorist, having heard any incomprehensible sound made by the car, for example, a click or knock in the front suspension area, experiences unpleasant associations. When heard, this is a clear sign that there is a problem in the chassis of the car. If the suspension of the car rattled, then you need to immediately produce parts of the car.

The main reason for the failure of the car's suspension is, of course, a broken road, the suspension breaks most often due to very unpleasant "surprises" such as pits and ditches. The suspension starts knocking after the car flies into a hole or a bump, the suspension also breaks due to inexperience, when some drivers notice a pothole at the last moment, and immediately press the brake pedal to the floor and do not release the pedal when the wheel hits into a pothole - during braking, the load on the rack increases several times and, accordingly, the suspension also suffers several times more. A considerable influence on the operation of the suspension is given by the angle of rotation of the wheel during contact with the pothole, and the reason is the same, increased load.

What suspension elements need to be diagnosed

So, what should be done if it appeared, and also let's talk about the reasons for its occurrence. First of all, you need to clarify something ... If the suspension rattles, then this is the result of a malfunction or malfunction of any part or chassis mechanism, for example, the following may fail:

Suspension Diagnostics

1. shock absorber;
2. Spring;
3. Spherical bearing;
4. Lower arm with silent block;
5. Upper suspension support with bearings;
6. Stabilizer link;
7. Stabilizer support;
8. Steering rack;
9. Tie Rod;
10. Steering tips;
11. hub bearing;
12. Steering cardan;
13. CV joint (outer hinge).

It will not be possible to determine the malfunction by ear, and to find the source of this knock in the front suspension, in order to find the malfunction, it is necessary to conduct a thorough diagnosis.

Visual diagnostics of the front suspension

Before proceeding to check the suspension parts, you must first inspect all the anthers and rubber boots of all the listed parts, as well as: silent blocks, ball bearings, front suspension arm, anti-roll bar, steering knuckle, mounting bolts, as well as steering tips thrust. As a rule, a part whose boot is damaged must be replaced.

It is also necessary pay attention to rubber seals, there should be no mechanical damage on the seals. Particular attention should be paid to those places where the parts are adjacent to the body.

When oil smudges are visible on the shock absorber, these are the very first signs of a malfunction, since they appear much earlier than other symptoms, such as scratches and extraneous sounds during rocking, it should also instantly dampen vibrations, and not sway, as happens with gradual failure. For some time, the shock absorber may still work fine, but it will still be better if it is replaced.

Checking the elements of the front suspension

Sagging (worn springs) on the performance of the suspension as a whole have a great influence, and when the springs are tired, it can be quite easily determined without tricky diagnostics, it is enough just to carefully examine the car from all sides and pay attention to the landing of the car if it has become lower than usual, that is, the springs have already served their purpose and require replacement. With sagging springs, it becomes impossible to properly adjust the camber.

To check the ball joints, you can check how the lower arms move up and down. Such verification must be carried out on a viewing hole using the mount. There should not be any noticeable backlash.

By pressing the mount on silent blocks the lower levers should also not have any backlash, and cracked or squeezed out pieces of rubber are not at all acceptable. It is also worth paying attention to how the rubber exfoliates or not from the outer or inner sleeve.

How to diagnose suspension

For check ball and silent blocks, you will need to raise the car on a lift or jack and unscrew the fastening of the ball joint to the lower arm, then turning the body of the ball joint with your hands, determine how smoothly and with what effort it turns, any backlash is unacceptable. The lower arm, due to the effect of the elasticity of the rubber of silent blocks, should try to take a horizontal position.

Bearing failure can often be determined by rocking the machine up and down; if unsuitable, they will have backlash. It is not always possible to identify a broken rubber part in a suspension mount without removing the mount.

Therefore, when visually checking stabilizer links and supports you need to swing your arms with effort.

Backlash is not allowed on all connections.

A steering rack malfunction is quite rare; its failure is mainly due to wear of the guide bushing on the side opposite to the driver. To determine such a defect, you need to turn the steering wheel to the side and, taking it through the cover, swing the rail with your hands.

Check steering tips and steering rods you can check by turning the wheel left-right or with the steering wheel, but at the same time you need to simultaneously take hold of the part to be checked. The absence of what is on the tips, what is on the rods should not be observed.

With a faulty steering cardan, it can either play, or turn with some effort. It is necessary to ensure that the steering cardan is covered with a cover, it is advisable to pick up and put on it some kind of cover-cover if there is none. A hub bearing failure is accompanied by a hum when driving.

For check wheel bearing you need to hang the wheel and spin it or swing it from the top point, in the direction both away from you and back.

Faulty external CV joint makes a rather loud and characteristic sound accompanied by a crackling sound while the car is moving in a sharp turn with little acceleration.

Front suspension may also have a number of other faults, but only the most typical ones were considered.

detailed car suspension diagnostics on their own, will make it possible to identify a malfunction without spending extra money and time and begin to eliminate the defect and repair the suspension. The verification process can be carried out both in your garage on a viewing hole or just on the street. Having carried out diagnostics on your own, you can conclude whether the car's suspension needs capital and the replacement of some parts of the nodes or a slight tightening of the bolts of the connections.

In conclusion, I would like to say that by finding running gear malfunctions, you should not delay with its repair, since your own safety and the safety of your passengers on the road directly depend on the condition of the car's suspension.

12.09.2016

Good day dear readers of the site Autoavenue, today I will tell you how to check the suspension of a car yourself, and understand what parts need to be repaired or replaced.

In order to start diagnosing, you will need a garage with a pit, a lift or a flyover. The goal is to be able to inspect the car from below. It will also not be superfluous to get gloves, a crowbar or a crowbar. If this is the first time you see your car in this perspective, do not be afraid, despite the apparent complexity of the suspension device, it consists of typical elements.

Let's look at the most unreliable of them:

• Ball bearings - used at the points of movable T-shaped joints.
• Silent blocks and bushings are rubber bands inserted into bolted joints to dampen vibration and noise.
• Anthers are such rubber covers that cover the nodes from dust, water and dirt.
• Stabilizer struts - consist of steering knuckles, and serve as a connector for the ends of the stabilizer with the main suspension element
• Oil seals are rubber rings that are installed in assemblies to retain oil in the place where the shafts or moving parts rotate.
• Bearings, springs, and suspension struts.

Recommendations on how to check the suspension of the car yourself.

The diagnostic procedure is standard and quite simple, but let's talk about everything in order:

1. To begin with, conduct a visual inspection, the left and right parts of the suspension are assembled symmetrically, so when comparing them, pay attention to whether all the details and fasteners are in place. If something is missing, then driving such a car is very dangerous.
2. Shake the hung wheels in the vertical and horizontal planes, there should not be any knocks and backlashes, if they are present, check whether the hub nut is well tightened. Then firmly grasp the wheel with both hands and slowly begin to turn it, while slightly rocking. This is how the wheel bearing is checked for wear, if there is even the smallest backlash, or rotation occurs with wedging, the bearing needs to be replaced.
3. Inspect absolutely all the anthers of the front and rear suspension, they should be intact and elastic, if you see cracks or tears, then such anther needs to be replaced as soon as possible (if this is not done, quite expensive components, such as an inner or outer CV joint, will need to be replaced soon etc.).
4. Necessarily check the brake hoses, no cracks or leaks are allowed if these defects have been identified, urgent replacement of failed elements is required. Brakes do not forgive slovenliness.
5. Pick up a pre-prepared crowbar or mount, and use them to check the ball joints. A bit of theory- the working part of the ball consists of a body, a pin and plastic liners, it is the plastic insert that wears out during operation. Your task, using multidirectional efforts, is to understand whether there is wear or not. To check, you do not need to apply a lot of effort, and during the wiggle there should not be any backlashes and knocks, if backlashes are present, the ball joint must be replaced.
6. The next objects of our close attention are silent blocks and bushings, if they are not in order, then when driving through bumps, sharp acceleration or engine braking, a thud will be heard. Checking them is quite simple, first inspect them visually for cracks and gusts, they should not be. Then we insert the assembly into the connection and carefully try to push the silent block. The new silent block is quite difficult to squeeze.
7. Now we evaluate the condition of the oil seals, they are installed in the main units of the car. For example, in an engine, gearbox, gearbox or steering rack, and are responsible for keeping lubricants at the exit points of rotating or moving parts. If you see traces of oil leakage from the unit or its fogging in the places where the oil seal is installed, it must be replaced.
8. Finally, inspect the shock absorbers and springs. The springs must be whole and equal in the number of turns on the left and right, and the racks must have whole anthers and no traces of oil leakage. If their condition is suspicious, then you should be checked at a car service at a specialized stand, or show the car to a qualified mechanic. Be aware that worn shock absorbers can cause a serious accident when maneuvering or braking hard on rough roads.

   

Summarize:

Try to do suspension diagnostics every six months when preparing the car for the winter and summer seasons. This will not only identify and eliminate breakdowns in the early stages, but will make traveling by car safer and more comfortable for you and your passengers.

The monotonous squeaks and taps coming from the front suspension while driving are a serious cause for concern. The car itself hints at the existing problems of the running structure. So that further trips do not end sadly, it is better to hurry up with finding out the nature of the occurrence of knocks. It is not necessary to immediately rush to a car service, it is more than realistic to independently examine the front suspension in a garage.

Why is there a knock?

Imperfect road surface - this is the main culprit of the "celebration", because the suspension plays the first role in the relationship between the road and the design of the car. It is she who takes the whole blow from road potholes. Even with careful driving, over time, the mechanisms are subject to wear.

Various parts of the chassis can make sounds:

• Shock absorbers (wear, pollution, insufficient fluid);
• Worn tips, seals or cracked rubber on them;
• Bearings;
• Traction (transverse, longitudinal);
• Departed mechanisms in contact with the body;
• Lost elasticity springs on the racks.

Given the above variety of noise sources, a comprehensive diagnosis of the front suspension is a reasonable solution.

Complete self-diagnosis of the front suspension in a garage

Helpful advice

An important condition: the garage must be equipped with an observation deck, only in this way a full overview of all the mechanisms of interest will open. If there is no hole, you can raise the front of the car with a jack, but this alternative method can hardly be called convenient.

The car is installed on the inspection hole and is ready for diagnostics of the following mechanisms:

1. Ball joints are the connecting element between the arm, hub and shock absorber strut.

How to check?

The front wheel must be hung out and loosened with both hands from side to side in the transverse direction. In the process of rocking, unsteadiness or play occurs - the ball joint has worked its way out, and it is definitely time to replace it. In addition, the wear of this part provokes steering vibrations, which complicates control. Do not lose sight of the condition of the anthers. The presence of cracks and deformations on the rubber is unacceptable.

2. The performance of silent blocks is easy to check by pressing the lever hard through the spatula (crowbar, mount). A sure sign of a malfunction is rubber that has appeared.

If the lever is in the form of a collapsible mechanism, then the silent block can be replaced as follows:

• Remove the lever, and clean the landing site from dirt;
• Squeeze out the silent block from the socket. First, you can remove the bushings, then file a little along the metal clip without hitting the lever;
• Press the new silent into the lever, after lubricating it with oil.

3. Spring and shock absorber. The most accessible way to diagnose the racks is to alternately swing from side to side in front of the machine. In order to feel the tapping, the palm must be applied to the rack, its surface is outside the engine compartment. Also, when inspecting the shock absorbers, you should pay attention to the oil - if there is a leak, this is a bad signal.

Spring wear is visible to the naked eye. It is given out by the presence of deformation, the resulting cracks and loss of elasticity. A visual inspection is also sufficient for the bearing, if its integrity is compromised, it must be replaced.

4. Malfunctions in the steering system are dangerous, making it difficult to drive a car, especially when cornering. Here you need to check the rods and tips for wear and gaps. It is the gaps that provoke a knock when driving, especially on rough roads.

Diagnostics:

• Steering tips are best checked with an assistant who will make sharp movements with the steering wheel from side to side. In the meantime, the task of the motorist is to find out if there is a backlash or not. To do this, you need to put your hand on the surface of the tip - a knock will be clearly audible;
• Steering rods are checked using the same technique. The goal is to identify gaps in the swivel joint.

To replace these elements, you must have a set of open-end and box wrenches, as well as a puller. Before proceeding with the procedure, the mechanisms are cleaned of dirt, the connector area is processed with a liquid key.

5. If a knock is heard during the ride, and when you press the brake it disappears, and appears again after releasing the pedal, the brake system is definitely naughty.

Existing brake pad problems can be verified as follows:

• Using a jack, raise the car, unscrew the wheel;
• Unscrew the brake disc, caliper and hub at the same time;
• Pay attention to the lining: if it is cracked, crumbled or peeled off altogether, the replacement of the brake pads is inevitable.

Below you can watch a video on how to diagnose the front suspension with your own hands in a garage.

We will not discuss and emphasize the importance of suspension for a car. This is the same important set of mechanisms and assemblies in a car, like any other. We only recall that the suspension (suspension system) plays the role of a link connecting the frame or the supporting body of the car with the road. Structurally, the suspension is part of the chassis of the car.

How suspension diagnostics are carried out

There is no need to say that the serviceability of the suspension, its parts and assemblies is a safe movement, and movement in general. A malfunction of any suspension part leads to unpredictable consequences, or rather, the consequences are the impossibility of movement or damage to the car body, and body repair is not a cheap pleasure. And if only - at best.

As always, there are several options for your consideration. It should be noted, however, that one does not exclude the other. And you can judge the effectiveness of any of them only after you try them.

Do-it-yourself suspension diagnostics in the literal sense - this is the "grandfather" way that came to us from the time of the Zhiguli and Muscovites. This is when we rock the stern of the car and let it go. After this procedure, the body makes 1.5 pitching, i.e. full up and slow down. Thus, we confirm . The old rattling noise specialists around the rear suspension can tell you what to look out for. Alas, this method of diagnosing the suspension is in no way suitable for modern cars.

Suspension computer diagnostics- this is a high-tech work, but it is applicable only to electronic control systems. This means that it is not suitable for obsolete car models, of which there are still a considerable number on the roads of the country. This type of diagnostics involves reading data from sensors, and gives recommendations as a percentage of the factory settings.

Vibration stand for suspension diagnostics- this is another way to check the condition of the nodes in conditions close to the road. The trouble is that the stands of different companies are set to different parameters, but they always require one thing - before the suspension is diagnosed at the stand, the car must be brought into good technical condition.

Those. comparing the results obtained from the shaker with the factory parameters of a particular model embedded in the computer, we end up with completely useless information. And what is most interesting on different services, the data can radically differ.

How to diagnose the suspension with your own hands

The way out of the situation suggests people's experience. You should pay your attention to the fact that the diagnostics of the front suspension requires special attention of the car owner. This is approximately the same as with the diagnosis of the front and. It is in front of the car that it experiences loads that are much higher than the loads on the rear of the car.

Traditional suspension diagnostics

• First of all, we check the anthers and rubber covers. It is accepted that a part with a torn rubber cover definitely needs to be replaced (repaired)
• Check for signs of oil leaks. This primarily concerns the diagnosis of shock absorbers
• The degree of wear of the springs is visually determined by the height of the subsidence of the car body
• Ball joints - are checked using a mount by rocking up and down. In this case, there should be no noticeable backlash.
• Silent blocks should not have visual deformation, cracks and delaminations. When pressed with a mount, they should not play. Checking ball and silent blocks is best done on a raised machine with the ball mount unscrewed to the lower arm
• The bearings of the upper suspension mounts, when rocking up and down, have play if they are faulty.
• Supports of stabilizers and thrust with increased swinging should not play
• Steering rack failure is not a common occurrence. The serviceability of the guide bushings is checked by swinging the rail itself.
• Tie rod and steering tip are checked together. The partner turns the steering wheel left and right, and at this time you take the part with your hand. Neither the tip nor the rod must have play.
• The CV joint warns us of its malfunction with a characteristic crack while driving, especially when turning.