printable version

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, on the contrary.

By analogy, the transverse pivot axis tilt angle is called a wheel angle deviation from vertical imaginary pivot in a plane perpendicular DP vehicle.

Discrepancy in turning steerable wheels is the difference between the angles of rotation of the inner and outer wheels when first rotated at a predetermined angle.

Terms of checking wheel alignment

Check alignment of the car requires a specially equipped rack / lift. 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.