Knocking in the front suspension when passing irregularities often becomes the first signal that the resource is not a resource. plumblock Or the ball supports came to an end, requiring immediate diagnosis. Ignoring these sounds leads to accelerated rubber wear, rudder beat and, in critical cases, loss of handling at high speed. Understanding what exactly running-piece They require attention, allowing the driver to avoid expensive repairs and to protect themselves on the road.
Car owners often confuse the symptoms of malfunctions by attributing knocking to shock absorbers, although the problem may lie in broken stabilizer bushes. Accurate knowledge of the chassis design helps to correctly formulate the request in the auto parts store and understand the mechanic who will conduct the diagnosis. Below we will analyze the suspension device in detail, classify the main nodes and identify signs of their failure.
Design of the front suspension: the main nodes
The front suspension of a modern car is a complex mechanism that provides a connection of the wheels with the body and damping of vibrations. The central element here is shock-stackIt combines a spring and a damper responsible for attenuating the oscillations. It is this node that takes the brunt of road irregularities, so its resource directly depends on the quality of the road surface.
The mounting of the rack to the body is carried out through bearingThis allows the entire structure to be rotated with the wheel when the steering is in operation. Wear of this bearing often manifests itself as a crunch when turning the steering wheel in place. The lower part of the rack or separate shock absorber is attached to leverwhich in turn is connected to the rotating fist through a ball support.
โ ๏ธ Attention: The anther rupture of the ball support leads to rapid washing out of the lubricant and dirt, which can cause the wheel to suddenly detach from the lever on the move.
To stabilize the body in corners is used transverse stability stabilizerwhich is connected to the levers or struts of shock absorbers through rods and bushings. All these elements work in conjunction, and failure of one part often provokes accelerated wear of neighboring nodes.
Technical nuances
Suspension Types: There are several types of front suspensions, the most common is the McPherson design, where the shock absorber is a load-bearing element. In more expensive cars, a double transverse lever is used, providing better handling, but taking up more space.
Rear suspension elements and their features
The rear suspension can be made in the form of a dependent beam or an independent multi-link design, which directly affects the set of used spare parts. In simple schemes with a torsion beam, the main consumables are shock absorbers And the Silent blocks of the beams attaching to the body. This design is easy to maintain, but less comfortable on bad roads.
Multi-link circuit (art.Multi-link) is much more complex and contains a large number of levers: longitudinal, transverse and diagonal. Each lever is mounted through Silent blocks or ball supports, the number of which in the rear suspension can reach a dozen pieces per wheel. This provides excellent course stability, but makes the diagnosis and replacement of spare parts more time-consuming.
In rear-wheel drive cars, an important element of the chassis is gearboxIt is attached to the subframe through special pillows. Wear of these pillows causes vibrations and hums, which are often mistaken for problems with hub bearings. Also in the rear part are often located elements of the braking system, requiring regular inspection.
Steering mechanism and its connection to the running gear
Although the steering is formally a separate system, its elements are closely integrated with the chassis and affect its condition. The main node here is steering-rail, converting the rotation of the steering shaft into a forward movement of thrusts. Luft in a geared pair of racks or wear of the guide bushes leads to the appearance of free steering and knocking.
The transfer of force to the wheels is carried out through steering-rod And their tips. Tips are hinges that have a limited resource, and their backlash is a common cause of steering beating and uneven wear of the tire tread. When replacing tips, it is highly recommended to check the condition of the anthers of the steering rack, since their damage leads to expensive repairs.
Modern cars are equipped with GURG (hydro-amplifying) or EUR (electrical booster) In hydraulic systems, it is important to monitor the condition of the high pressure hoses and the level of fluid, since a leak can lead to amplifier failure and jamming of the steering wheel. Electric motors EUR, located on the shaft or rail, can also fail, requiring complex diagnosis.
- ๐ง The steering thrusts transfer the force from the reiki to the turning fists.
- ๐ง The tips of the steering rods regulate the convergence of the wheels and have a threaded connection.
- ๐ง The steering shaft cardinal connects the steering wheel to the rack and often has a cross.
- ๐ง The GUR hydropump creates pressure in the system, ensuring easy rotation.
Stage knots and bearings
The hub is the central element on which the wheel is attached, and inside it is located hub-bearing. This is a detail that experiences colossal radial and axial loads. A sign of wear of the bearing is a monotonous hum, increasing with increasing speed and changing the tone in the turn.
On front-wheel drive cars, an external hub passes through the hub ล RUS (a hinge of equal angular velocities) transmitting torque. SRUS dust is a critical detail; the slightest crack leads to the entry of abrasive and rapid destruction of the hinge, which is accompanied by a characteristic crunch with the wheels turned and acceleration.
The fastening of the wheel is carried out through studs or bolts, the condition of which also needs to be monitored. Damage to the seat under the bearing in the hub itself or the swivel fist requires the replacement of the entire assembly, since pressing a new part into a deformed hole is impossible.
Bearing Check: Lift the car on the jack and sway the wheel with your hands in vertical and horizontal planes. The lash and knock will indicate a malfunction of the bearing or ball support.
Brake system as part of running system
The effectiveness of braking depends on the state of the elements fixed on the chassis. The main consumables here are brake-pad and brake-discs. Wearing the pads below the permissible limit leads to damage to the discs and reduced braking efficiency, especially in rain.
Brake calipers that press the pads to the disc have guides that must move freely. Souring guides is a common problem leading to uneven wear of the pads and the car moving aside during braking. Regular lubrication of guides with special compositions prolongs their life.
Brake hoses are an important safety element. Rubber ages over time, becomes covered with cracks and can depressurize under pressure. Visual inspection of hoses at each wheel replacement or suspension repair is mandatory to prevent emergency situations.
| Detail | Resource (km) | Symptom of wear and tear | Consequences of neglect |
|---|---|---|---|
| Brake pads | 30 000 - 50 000 | Scream, screech, reduced efficiency | Disc damage, increased braking distance |
| Brake discs | 60 000 - 100 000 | Steering beat during braking | Disk destruction, caliper overheating |
| Brake fluid | 2 years / 60 000 | Soft pedal, boiling. | Brake failure, calipers corrosion |
| Brake hose | 100 000+ | Cracks, bloating. | Hose rupture, brake loss |
Diagnosis and signs of malfunction
Timely identification of problems with the chassis can save significant funds. The primary method of primary diagnosis is listening to the car while driving. Knocking, creaking, hum or whistle โ all these sounds carry information about the state of the nodes. For example, a thud on small irregularities often indicates wear of the stabilizer bushings.
Visual inspection also provides a lot of information. Cracks on rubber elements (silentblocks, anthers), oil leaks on shock absorbers, uneven wear of tires - all these are clear signs of malfunctions. Slanting tread wear often speaks of violation of the angles of installation of wheels due to backlashes in the suspension.
Professional diagnostics on the lift allows you to identify backlashes that are not noticeable during an external examination. The mechanic uses a mounting shovel to check the gaps in the hinges and connections. The regularity of such checks depends on the operating conditions: for city cars it is enough once a year, for SUVs - every 10-15 thousand km.
โ๏ธ Checklist for running checklist
Frequent questions about spare parts
How often do you need to change the Silent Blocks?
The resource of the Silentblocks depends on the material (rubber or polyurethane) and operating conditions. On average, rubber serves 60-100 thousand km, polyurethane can walk longer, but transmit more vibrations. They need to be changed when cracks, tears or knocks appear.
Can I drive with a broken ball support?
Absolutely not. The ball support holds the weight of the car and ensures the wheel turns. Its destruction in motion leads to breaking the wheel and uncontrolled skidding, which is deadly.
Do I need to go down after replacing the parts?
Yes, after replacing any elements that affect the geometry of the suspension (levers, traction, racks), be sure to check and adjust the angles of the wheel installation. This will prevent rapid wear of the rubber and ensure stability of management.
Which is better: original parts or analogues?
The original guarantees the matching of the resource, but often overpays for the brand. Quality analogues from proven manufacturers (Lemforder, TRW, CTR) may not be inferior in quality, but require careful choice, since the market is saturated with fakes.
Main conclusion: Regular diagnosis of the chassis and replacement of worn parts with pairs (on both wheels of the same axle) prolongs the life of the car and guarantees safety on the road.