How do running diagnostics. Car chassis diagnostics

The fact that any node in the car must be serviceable is beyond doubt. This fully applies to such an important part of the car as the suspension - its technical condition should always be perfect. It is responsible not only for comfort when driving on roads with a heterogeneous, low-quality surface, but also for safety. So, it is the suspension that is responsible for maintaining the horizontal position of the body when driving.

This is required to maintain control of a vehicle that makes sudden maneuvers, especially at high speeds. If there is a faulty or heavily worn element in the suspension of the vehicle, there is a real threat to the safety of the driver, his passengers, and other road users. Eg, sagging springs or damaged shock absorbers that are unable to ensure the stability of the car can cause a departure into a ditch when trying to overtake or entering a sharp turn. Their independent and timely diagnosis will avoid such problems.

How the suspension works

In order for the car suspension to always remain in a technically sound condition, it should be checked periodically by yourself. Suspension diagnostics can be carried out at service centers using special stands and computers, but this is not suitable for every car. In addition, the cost of such a service is a considerable amount. For the vast majority of owners of domestic vehicles, self-diagnosis of the suspension is the best option.

To correctly diagnose the suspension yourself, you need to know how it works. The main elements of any suspension, which are most often prone to failure, and therefore require special attention, are the following:

For experienced drivers who have been driving for many years, there are no problems with self-diagnosis of the suspension. Often, they just need to listen to the car while driving to accurately determine the faulty node. For inexperienced drivers or owners of luxury cars, where everything is controlled by electronics, everything is not so easy. However, suspension diagnostics must be performed.

Principles of self-diagnosis

Periodic diagnostics of all suspension elements is important for any car, but not all car owners do it. This is associated with a considerable amount of time, and with some inconvenience - it is better to carry out self-diagnosis by raising the car on a lift. However, the appearance of extraneous noise and knocks in the suspension when the car is moving forces most drivers to crawl under the car. This is a great alternative to a service check, because often the cause of a knock or rattle is just a penny gum seal, the replacement of which is a matter of several minutes.

The first priority for self-diagnosis of the suspension is a visual inspection of all protective covers, or anthers. Any experienced mechanic will tell you that an assembly that lacks boot protection is either in need of repair or will need it soon. It should be understood that the presence of cracks on the still whole anther, found during self-diagnosis, should be regarded as the need to replace it with a new one, since it will cease to perform its direct duties in the near future.

After diagnosing anthers, you can start diagnosing the front suspension - it is more susceptible to damage, since it is the first to encounter all the flaws in the road surface. Diagnostics of shock absorbers consists in their visual inspection - no visible deformations are allowed on the body, as well as oil smudges. Do not confuse this with oil deposits, the presence of which is considered the norm. The serviceability of these elements can be judged without inspection - just shake the car standing on the ground. If it continues to sway on its own after the driver no longer makes an effort for this, then it's time to change the shock absorbers.

Important! When diagnosing suspension springs, first of all, attention is drawn to the presence of visible cracks in them.

It is worth evaluating the height of the clearance, if it is less than normal, then the springs also do not perform their functions and require replacement. Ball and silent blocks are diagnosed with the car raised. There should be no pronounced play, deformations and delaminations. There should be no play on the stabilizer supports, rods and bearings. The same moment is checked on the steering rod. Carrying out independent diagnostics of the front or rear suspension, it is advisable to pay attention to the brake system - primarily discs and pads. A few tips for self-diagnosis - on the video:

How suspension failures manifest themselves

To suspect that the suspension is not working correctly, you do not need to be an experienced mechanic - often car diagnostics are not so difficult. Especially if the car was purchased new, and the memory of a smooth, comfortable and quiet ride has not yet been erased from the memory of the car owner. Of course, the quality of the road surface in many regions of our country is far from ideal, but there are a number of signs, the presence of which is the reason, at least, for a simple visual diagnosis of the suspension. These calls include the following:

Basically, any of these symptoms is already a reason for diagnosing the suspension: computer or independent. Operating a car with a faulty suspension is not only unacceptable by the rules, but also simply dangerous. In addition to the immediate threat to life and health, postponing the diagnosis of a car and its repair for later often leads to the need for very expensive and lengthy repairs in the future.

The most common faults

The main number of suspension failures of any car occurs as a result of a tangible mechanical impact that continues all the time while the car is moving. Bumps on the unevenness of the road surface causes incessant mechanical stress, as a result of which certain defects appear even on metal parts, making the normal operation of the suspension impossible. Among the most common and characteristic breakdowns of standard suspensions, which are easy to determine with self-diagnosis, include the following:

• disturbed balancing of wheel alignment-camber;
• loss of design stiffness by springs and shock absorbers, and in case of serious overloads, their complete failure;
• loss of suspension arms of the correct geometric shape;
• damage to silent blocks, ball bearings, bearings;
• breaks or severe abrasion of rubber seals.

What threatens the lack of diagnosis of the condition

The absence of an elementary self-diagnosis of the front and rear suspension cannot remain without consequences even for the most technically advanced car. Of course, we are not talking about the need to independently carry out diagnostics and interfere with the operation of a complex adaptive suspension, which is completely controlled by electronics. But the standard suspension options that most vehicles are equipped with require constant attention from the driver. Worn suspension significantly impairs the comfort of the driver and passengers during the trip, but this is the least significant consequence.

Improper suspension operation threatens the following troubles while driving:

• a noticeable increase in the braking distance, due to the high reactivity of the body, which allows for serious swaying when trying to brake sharply, as well as accelerate;
• poor car stability on the road, which is especially noticeable when maneuvering at high speed - too much body roll can lead to a complete loss of control over the car, especially on slippery surfaces;
• large loads on the load-bearing elements of the body, resulting from weak damping, accelerating its wear.

In addition, operating costs for maintaining a car increase, for example, uneven tire wear requires more frequent replacements, which can cost quite large amounts.

It is an important point not only when buying a car, but also when carrying out routine maintenance. Consider how to check the chassis of a car, determine the source of extraneous sounds, and also calculate the remaining life of some suspension elements.

Test Drive

Any test of the chassis begins in motion. Open the window to more accurately determine where extraneous sounds are coming from. Watch the behavior of the car on the road. There should be no yaw, excessive swaying on undulating sections of the roadway and roll in corners. Be sure to pay attention to the operation of the brake system.

At a speed of 20-30 km / h, turn the steering wheel in different directions. The appearance of clicks or crackling will indicate a malfunction of the CV joint or thrust bearing. With a static inspection, this malfunction cannot be detected.

To conduct a full inspection, you will need a lift and an assistant. A jack can be used to check the wheel bearings. The inconvenience is that you have to jack up each wheel. From the tool you will need: a crowbar, a mount or an ordinary piece of a strong pipe, a flashlight. Don't forget gloves.

Ground check

Ask the assistant to pull the steering wheel with sharp movements with a small amplitude. At this moment, listen for yourself to see if knocks come from the steering rack. If possible, pull the levers of the steering rack of the car. There must be no play in the vertical direction. The opposite will indicate broken bushings in the rack or a worn steering rod guide.

Steering rack malfunctions in the initial stage can only manifest themselves under certain conditions, so when you drive a new used car for you, you may not notice symptoms. Keep in mind that over time the problem will progress, resulting in the need for costly repairs.

For subsequent express diagnostics, you need:

• ask an assistant on a muffled car to turn the steering wheel in both directions until it stops. In this one, put your hand on the glass at the location of the support. If you feel, hear a crunch at the moment the steering wheel is turned, the car's swivel bearing has “ended”. You can also identify this by placing your hand on the spring. At the moment of turning the wheel, it should not “jump” or vibrate, and the turning movement itself should take place smoothly;
• turn the steering wheel all the way to either side. Inspect the boot of the CV joints. It should be free of grease and rips. Bending, in this position, you can inspect the anthers of the ball, steering tips;
• inspect the visible contour of the brake line. There should be no places of deep corrosion on the tubes, brake hoses should be free of torn;
• rock each side of the car. A serviceable shock absorber will return to dampen the oscillation in 1 movement. Otherwise, the machine by inertia will swing a few more times. Inspect the shock absorber rod for smudges and oil fogging. Such a defect indicates leakage of the stuffing box.

Lift check

Some running gear failures cannot be identified without hanging the wheels. After lifting the machine, perform the following procedures:

• rock the wheels back and forth in a vertical direction. If you find play, the wheel bearing is to blame. When driving, a malfunction is often accompanied by a hum at speed. A similar symptom may appear or disappear in turns. Spin the wheel. It should rotate without delay, rustling or crunching. Do the same movement, only in a horizontal direction. Backlash can be from a wheel bearing, steering tip or rack;
• lay the lever (mount, pipe, etc.) between the steering knuckle and the suspension arm. By applying force in the vertical and horizontal direction, it is possible to determine the presence of wear in the ball joint and steering tips of the undercarriage;
• stabilizer links should not play in the vertical and horizontal planes. Pull them with your hands or apply force with a lever. Apply force to the stabilizer link itself. If you find a significant backlash, then it is necessary to change the sealing bushings;
• one of the main elements of the chassis of the car - silent blocks. Their verification should be given the most attention. Start the inspection of rubber products by looking for tears or obvious signs of rubber delamination from metal bushings and clips. Using the lever, apply force in different planes. Elements fixed by whole silent blocks should make only small deviations, and then return to their original position again. In rocking, detachment or expansion of tears can be observed. This behavior is a clear message to repair the chassis of the car.

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An important step in getting to know the car that you want to buy from your hands is checking the chassis of the car. Chassis - a large set of mechanisms, some parts here are consumables, since this part of the car is movable, and its elements are directly responsible for contact with the road, steering and much more.

Even if the car is legally clean, and everything is in order with the main units like the engine, this is not a reason to rush and buy - look under the bottom, there are also enough vital elements for the car.

Those who are not ready to spend money on a diagnostic service in the service, reading, become thoughtful - how to independently check the running gear of a car? We will talk about this in detail and in detail.

Self-checking the running gear of the car

If you decide to check the car yourself, including to see what is under its bottom, it is important to know what to look for - there are four wheels around the perimeter of the car, in the middle most often there are crankcase protection sheets, but this does not mean that you can’t look there for what.

First of all, faulty suspension elements give themselves out as extraneous sounds. If extraneous sounds are heard below, then the culprits requiring replacement or repair may be:

• Shock absorbers - an element that takes on all the bumps and bumps from road pits;
• The springs of the racks are constantly loaded, over time they inevitably “get tired” and require replacement;
• CV joint boot - as the name implies, protects the part from dust. If it is dirty or torn, a replacement is required;
• The support cups of the racks - by and large, just need to be intact and not deformed;
• Silent blocks are what connects various parts of the suspension. It consists of two metal bushings with a rubber insert in the middle. If, when driving, there are strong vibrations from the suspension elements, and the car is not too stable, questions should arise first of all to this element;
• Various backlashes - they can touch many elements of the running gear at once, be it CV joints, tie rod ends and much more.

It is worth dwelling on some points to clarify the details, especially if many of these words have become something new for you.

Shock absorbers are the simplest, no special skills and abilities are needed here, and anyone can check their condition on the spot. To do this, just try to rock the car, if it rocks more than two times - the shock absorbers need to be replaced. To make sure that they are completely faulty, you can lift the car and inspect them from the side for smudges.

With springs, it is somewhat more complicated - the fact that the springs "sagged" may not be visible to the naked eye, unfortunately. But it is very clearly visible if the spring is broken. Yes, and the suspension height of the car, in which case it will hint - if the car is too low, then you should pay attention.

With anthers, everything is simple - if it is whole and clean, then we move on, if it is dirty or torn, or all together - we change it. The part is not too expensive, even cheap (what can be expensive in a piece of rubber?), so torn and dirty anthers are only a cause for concern if the owner has been driving with them in this condition for a long time.

Buying a self-diagnosed used car involves getting your hands a little dirty and inspecting the car from top to bottom. Some parts of the chassis need to be checked more carefully and in several stages, since it will no longer be possible to determine the problem “by eye”.

For example, a silent block. Here everything is a little more complicated and you have to tinker if you want to know everything and for sure. If you checked the car on the move and noticed that the car “pulls” to the side while driving, then the algorithm for checking the silent blocks is as follows:

• Raise the car with a jack, but it is better to drive it into a viewing hole;
• While the car is suspended, remove the ball joints to get to the silent blocks;
• Check the condition of the parts working in conjunction with the silent block. This is a suspension arm that you can swing back and see if it bounces back. Check the sleeve, it does not rotate relative to the lugs. After that, check the silent block itself for knocking;
• It is important to check the element for play and mechanical damage. If the element is too mobile, or if it is damaged on the metal parts or on the rubber, one should consider replacing the entire element.

If you are not afraid to take on the installation, you can, being under the car, check the condition of the stabilizers. If you stick the crowbar between the subframe and the bushing stabilizer and shake it, you will understand whether the elements are working or not. A bushing that is too old will cause the stabilizer to “walk” due to deformation. This indicates the need for replacement. However, for this procedure, you still need a lift, if you have in mind - use it, but it would be better to go to a service where the procedure will be carried out for a modest fee.

In the case of the brake system, everything is simple if the car is on cast or forged discs. If you are considering a simple option with "stamping", here you can no longer do without removing the wheel and studying the elements of the system.

The condition of the brake pads is important - they must not be rusty or worn out. Otherwise, they must be replaced. The same applies to the brake disc, and here you can use a caliper, since the set thickness of the brake disc is different for different cars, and the easiest way to determine the condition is by ordinary measurement.

The last thing I would like to mention cannot be attributed to any particular element, this applies to many elements at once, and in some cases can lead to serious consequences.

Examine the chassis for a variety of backlashes. To do this, you need to find out how mobile certain suspension elements should be, and with your own hands check how mobile they are on the car. Any play above the norm needs to be eliminated, and in some parts a large play (for example, in the steering) can be dangerous both for the car and for the people in it.

Contacting the service

Another, simpler, but less economical option, how to check the running gear of a car before buying, is to pay for running diagnostics in a car service.

Here, the plus is not only that you don’t have to crawl under the car yourself and check the elements for play, but also that the diagnostics are usually complex, and you will be told not only about the chassis, but also about other important details and technical aspects of the car.

If you want to thoroughly know everything about the chassis and suspension of the car after checking, then ask the masters to check the chassis point by point to get information about its most important elements:

• shock absorbers;
• Levers;
• Pivot pins (knuckles);
• ball bearings;
• Springs;
• Anti-roll bar;
• Stabilizer's pole.

From the state of these elements of the chassis, conclusions are already being drawn and a decision is being made. The cost of complex diagnostics in the service is about 2-3 thousand rubles, and in this case, the masters will lift the car on a lift, study the suspension elements, and inform you about what to replace and what kind of repairs the car and its chassis require.

Checking the chassis will tell both about its condition and how the car was cared for in general. Not a single motorist who takes care of his vehicle will ever allow serious damage to the chassis and will not “start” it. Cracked springs and torn anthers are a sign that the car has not been looked after and may be a reason to refuse to buy a car.

And do not forget to check the history of the car before buying. This can be done using the Autocode service according to the state. number or VIN. The check is carried out according to 16 official sources: the traffic police, the RSA, EAISTO, the Federal Tax Service, the Federal Customs Service and others. In 5 minutes you will learn about all the problems that a car has: twisted mileage, the presence of a traffic police restriction, being wanted, a loan or arrest, and much more.

If the online check gave a positive result, and the car is in perfect order from a legal point of view, we recommend that you study its technical component in more detail. To do this, it is best to use the services of an on-site car check. The specialist will arrive at the appointed time at the appointed place and inspect your car using special equipment. Thus, even the smallest hidden damages will be established.

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.

An article about the diagnosis of the chassis of a car - what the chassis consists of, types, stages and the diagnostic process. At the end of the article - a video about checking the chassis with your own hands.

The content of the article:

The undercarriage of the car is designed to move and control it, as well as to absorb vibration-shock loads on the body when driving on uneven road surfaces. Therefore, the diagnosis of "running" is the most important and necessary condition for comfortable and safe operation of the car.

After all, it is the “chassis” that is the main part of the design of the machine, on which ride comfort and traffic safety directly depend. You can drive a car with many malfunctions (electricians, body, engine), but it is precisely because of malfunctions in the chassis that the car can literally “fall apart in the middle of the road”.

In general, the diagnosis of the undercarriage of the machine can be divided into three options:

1. emergency(emergency) - when during the operation of the car a knock and clang in the chassis is already clearly audible, an extraneous knock when the steering wheel is turned. The car behaves unstably at high speed, gives a strong roll in corners, "jumps" in the pits. At the moment of braking, the car pulls to the side, and when accelerating, the steering wheel pulls to the side. That is, the “chassis” is so worn out that the operation of the car becomes uncomfortable and unsafe.
2. Planned– when running diagnostics is scheduled for a certain time and is carried out regardless of the condition of the vehicle. For example, an off-season diagnostic examination, before the start of winter or summer.
3. Prepurchase– diagnostics of the chassis of a used car before buying it.

Any running gear diagnostic option involves the same set of actions, most of which can be performed independently, without the involvement of a specialist. But, of course, before making an independent diagnosis, you need to know what, where and how to inspect.

The chassis consists of a complex of units, elements and mechanisms to which torque is transmitted from the engine (through the transmission and drive), as a result of which the car moves along the road. The main elements of the running gear are:

• load-bearing body (or frame);
• suspension (front and rear);
• bridge beams;
• wheels (with wheels and tires).

Additionally, there are many more auxiliary mechanisms and elements in the chassis: shock absorbers, ball bearings, levers, brake mechanisms, springs, anthers, silent blocks, etc. And each of these elements and mechanisms performs its own separate functions for moving the car, driving it, reducing vibrations and vibration load when driving over bumps. The main part of the additional elements is located on the pendants.

The most worn out "consumable" elements of the undercarriage

The following elements of the undercarriage, which are also called “consumables”, are subject to the greatest and fastest wear:

• ball joints– hinge-type fasteners, with which the suspension arm is attached to the wheel hub.
• stabilizer bar- a thin rod that has steering knuckles and connects the ends of the anti-roll bar to the middle part of the suspension.
• Shock absorbers, hydraulic struts and springs- are buffer parts between the wheels and the suspension and serve to mitigate the shock load when driving on uneven road surfaces.
• Mounting rubber bushings– are located in connections with bolts. They serve to absorb shock and vibration loads and perform hinge functions.
• Silent blocks– rubber-metal hinges for suspension arms.
• Rubber covers(anthers) - resemble an accordion. They serve to protect joints from road dust and corrosion.
• Oil seals- rubber rings to prevent oil leakage in the nodes.

Also, bearings and hubs are subjected to great wear, which significantly affect the handling of the car. Therefore, they should also be checked frequently.

Chassis diagnostic steps

Diagnostics of the chassis of the car is best divided into two stages:

• When moving.
• In place (static).

Diagnosis of "running" while driving is quite simple. All that is required of the driver is attentiveness. It is necessary to observe the behavior of the car at speed and during braking, as well as to detect extraneous abnormal sounds (knocking, grinding, creaking, etc.) by ear when driving on a normal good and bad dirt road. For example:

1. When driving at high speed, the car becomes unstable. There is also an increase in steering play - problems with the steering rack or with the tie rod mounts.
2. When driving on the highway, the car leads to the side - the wheel alignment is not adjusted. Different tire pressures. Various tires. Sometimes the cause can be a deformed body.
3. When driving, vibration is felt in the steering wheel - the wheels are incorrectly balanced. Worn or tight wheel bearings. Deterioration of the steering gear joint. Loose wheel nuts. Deformed rim.
4. When the steering wheel is turned in different directions, at a speed of 20-30 km / h, clicks or creaks are heard - the constant velocity joint (CV joint, which is often called a “grenade”) is faulty. Also, these sounds may indicate a malfunction of the support bearing.
5. When cornering, a strong body roll is felt - the stabilizing system of the chassis is faulty.
6. When braking, the car moves to the side, the braking distance increases - the brake pads or drums are heavily or unevenly worn.
7. When driving on a rough (especially unpaved) road, a knock is heard in the area of ​​\u200b\u200bthe wheels, under the wings of the body - the ball joint is worn out, the shock absorber is faulty or its rubber mounting sleeve is worn out. The hydraulic strut may also be faulty (“knock out” when fluid leaked out of the strut). The spring may be broken. If a knock is heard from behind, the shock absorber, spring, rubber mounting sleeve, or rear strut are also likely to be faulty.
8. A dull knock during rapid acceleration - silent blocks are worn out and have lost their elasticity.
9. When driving on a flat road, a rumble is heard - the hub bearing is worn out.
10. Squeaking when braking when cornering - shock absorbers are faulty or stabilizer bushings are worn out.

For a more thorough self-diagnosis of the "running" one will need an inspection hole (in the garage) or a special flyover (on the street). You will also need:

• jack (or hydraulic lift);
• ordinary screwdriver;
• mount (or crowbar-"crowbar");
• flashlight;
• gloves.

If possible, it is better to use a lift, as in a car service. In addition, the presence of an assistant is desirable. And, of course, the bottom of the car, and the elements of the chassis must be more or less clean, so that when viewed from above, dirt does not fall, and the elements being inspected are clearly visible.

1. It is better to start a general running gear diagnostics with the front suspension. by lifting the hood cover to inspect the upper strut mounts. It is important here that the car is standing, not hanging, as the suspension must be loaded. It is necessary to check the gap between the cup and the body with a screwdriver. If the screwdriver freely enters the gap, and the size of the gap itself is 1.5 cm or more, then it's time to change the top cushion.
2. You can immediately check the support bearing by holding the stem with your hand and shaking the front end in different directions. If play is felt, then the bearing is worn and is a source of knocking when driving on rough roads. Especially well the knock is heard when driving through the speed bump.
3. At the same time, here you need to check the performance of shock absorbers and hydraulic struts. A sign of their malfunction will be the buildup of the machine. To detect the buildup, you need to press on the top of the wing with your hands and release it sharply. If the front end smoothly returned to its original position, then there are no problems with the shock absorber or strut. If the front end did more than two rolls and jumped like a ball, then there is a problem with the shock absorber or hydraulic strut.

   Such a simple procedure is often done even by not very experienced motorists when buying a used car. If you suspect a malfunction of the shock absorber or hydraulic strut, a closer inspection of these parts will be required with the machine raised by a jack or on a lift.

   
   Visually, a malfunction of a strut or shock absorber is determined by the flow of fluid from them. Also visually (or through buildup) you can determine the wear of the rubber mounting sleeve of the shock absorber, due to which knocking can also occur.
4. Now you need to raise the car with a jack (or a hydraulic lift, or on a car service lift) and shake the front wheels “to break”. In this way, you can detect the knock of the steering rod, its tip or ball joint. To more accurately determine where it knocks and there is play, an assistant may be required. While one will shake the wheel, the second one will be able to determine the exact location of the malfunction by touch.

   Also, the critical wear of the ball joint can be determined by swinging the lever by hand near the support itself. If there is not enough strength to determine the backlash, then you can use a mount (or crowbar). To do this, the mount must be inserted between the fist and the lever, and then shake. With a working ball joint, there should be no backlash and knocking.

5. Simply spinning the wheel will determine wheel bearing wear. If there is a rumble or rattle during rotation of the wheel, the bearing must be urgently changed.
6. Diagnosis of the rear suspension must begin with the wheels, same as before. Ball joints and tie rods at the rear do not need to be checked, because they are not there. Wheel bearings are also checked by scrolling and shaking the wheel “for a break”. If there is no rumble during rotation and play during reeling, then the wheel bearing can be considered serviceable.
7. At the last stage (or in progress) all rubber elements are inspected: silent blocks, anthers (covers), mounting sleeves. There should be no cracks or damage on silent blocks. Also, they should not give excessive play and be easily squeezed when the lever is moved using the mount.

Anthers (have the appearance of an accordion) should also not have cracks and destruction. A cracked but not yet torn boot can still be used for a while, but it is better to replace it as soon as possible. Sometimes the anthers lose their elasticity, as a result of which grease begins to seep out from under them. Such anthers (as well as torn ones) must be changed immediately.

Mounting sleeves not only take on shock loads, but also act as hinges for the mobility of suspension elements. Accordingly, they are subject to destruction and erasure. If the protruding edges of the rubber bushing (on the linkage, suspension arm or shock eyelet) are cracked, then the bushing must be replaced. Also, the sleeve must be replaced if the finger has shifted from the center of the lug to the edge.

Conclusion

Self-diagnosis of the chassis of the car is undoubtedly useful and helps to save a lot of money. After all, there are many car owners who are able to fix problems in the chassis on their own.

However, it should be remembered that a full-fledged “running” diagnostics is possible only if you have the appropriate knowledge of the car’s structure and using professional bench diagnostic equipment in a specialized service station.