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Corners of installation of wheels of the car - the general information

The angles of the wheels greatly affect the stability of the car, tire wear and fuel consumption. Nominal values of the angles are given in the Specifications.

It called the collapse of the angle of the plane of the wheel relative to the vertical. If the wheels are inclined upper edges outward collapse is called positive, and vice versa. The magnitude of the collapse is measured in degrees. A correct control of the collapse determines the amount and position of the contact patch with the road surface protectors, and to compensate for changes in suspension geometry that occur during cornering and when driving over uneven pavement.

Convergence (convergence) is the quantity information to each other of the front edges of the wheels of the car. Such a violation of the parallelism of the wheels to minimize tread wear by preventing skidding when cornering. At zero convergence distance between the front edges of the wheels is equal to the distance between their rear edges. Normal convergence is not usually exceed a fraction of an inch (1 inch = 2.54 cm). Infringement of adjustment of convergence leads to accelerated wear of tire tread by slipping them on the pavement.

Coasting is the angle Caster / wheel axis of rotation, ie, the angle of deviation of the axis of the vertical plane of the wheel rim. If the axis of rotation / pivot tilted back, the stick is called positive, and vice versa.

By analogy, the angle of inclination of the transverse axis of the wheel turning angle deviation called imaginary pivot in the vertical plane perpendicular to the plane of symmetry of the vehicle.

The value of the limiting angles of rotation of the front wheels of the car should be reduced by increasing the size of the latter. The distance from the edge of the tire wheel turned fully to the trailing arm should be around 2 cm, otherwise a corresponding adjustment is necessary (see. Section Check and adjustment of limiting rotation angles of the front wheels).

General check suspension geometry is carried out on a special stand in a specialized workshop.

Terms of checking wheel alignment

Check alignment of the car requires a specially equipped rack. Before you start scanning, you must ensure the following conditions:

• Tyre pressure corresponds to the nominal;
• The front wheels are mounted in a straight line;
• The car is loaded, the fuel tank is completely filled;
• Suspension elements Car upset with the effort;
• Steering gear properly adjusted;
• Play in the tips of steering rods and ball bearings suspension does not go beyond the limits;
• The depth of the tread of tires mounted on the wheels of one same axle.