Sequence of execution of the check
1. Before each trip, carefully inspect the wheels of the car and their fastening elements. Each wheel is attached to the hub with four bolts. Press vigorously on the side of the wheel with your foot, rocking the car in the transverse direction. If the wheel fastening bolts are not tightened, it will begin to swing on the hub. At the slightest suspicion of a loose wheel fastening, check the tightening of the bolts (for tightening torque, see. "Wheel - replacement"). Wheel disks must be free of cracks and signs of deformation. The tires must not have cuts, delaminations, tears, swellings ("hernias"), or protruding cords.
Note: If there is no mechanical damage to the tire, its suitability for use is determined by the height of the tread pattern.
2. We visually determine the possibility of further use of the tire based on the indicator protrusions in the grooves of the tread pattern.
The lugs are 1.6 mm high. Once the tread height is equal to the lug height, the tire should be replaced.
3. The indicators are located around the entire circumference of the tire at some distance from each other. We find them by the conventional designations in the form of the letters "TWI" or the arrows "up" on the sidewall of the tire.
4. The remaining height of the tread pattern is determined by eye or using a depth gauge caliper.
Thus, it is possible to compare the degree of tread wear at the edges of the tire and in its center. Accelerated wear of the middle part of the tread indicates the use of the tire with increased pressure, and rapid wear of the inner or outer part of the tread indicates the need to adjust the wheel alignment angles. If one of the wheels is intensively worn, it is possible that the suspension elements or the power elements of the car body are deformed.
Warning. According to the "Appendix to the Basic Provisions for the Admission of Vehicles to Operation and the Duties of Officials to Ensure Road Safety", it is prohibited to operate a passenger car:
- if the tire tread depth is less than 1.6 mm;
- with tires that have external damage (punctures, cuts, tears) exposing the cord, as well as delamination of the tire carcass, separation of the tread and sidewall;
- if there is no mounting bolt or there are cracks in the wheel disk and rims, there are visible violations of the shape and size of the mounting holes;
- if the tires do not match the vehicle model in size or load capacity;
- if tires of different sizes and designs are installed on one axle of a vehicle (radial, diagonal, tubed, tubeless), models with different tread patterns, studded and non-studded, frost-resistant and non-frost-resistant, new and retreaded tires.
5. The appearance of vibration felt on the body or steering wheel when the car is moving at a constant speed of over 80 km/h may be a consequence of an imbalance of one of the wheels. To identify the cause, check the wheel balance at a tire shop. If the vibration is caused by a deformation of the disk, damage to the tire or uneven wear, replace the tire or disk.