On the importance of four-wheel positioning, when should we do four-wheel positioning?
For many people, the biggest concern after buying a car is the repair and maintenance of the car. In addition to the regular large maintenance, small maintenance, the most frequently heard is "you need to do this car four-wheel positioning." So, what exactly is four-wheel positioning? When do we need to do four-wheel positioning?
What is four-wheel positioning?
In order to ensure the stability of the car running in a straight line and the ease of handling, reduce the wear of automobile tires and other parts, must consider many factors to determine the Angle of the wheel and the ground, steering wheel, steering knuckle and front axle three and frame installation should maintain a certain relative position, this has a certain position of the installation called steering wheel positioning, also known as the front wheel positioning. Before the usual wheel positioning refers to the front wheel positioning, now the vehicle in addition to the front wheel positioning also need to rear wheel positioning, that is, four-wheel positioning.
After the precise measurement of the vehicle through the special instrument, according to the measurement results and the original design standards, the vehicle after comprehensive diagnosis, adjustment, maintenance and other operations, in order to make the car back to the original standard, to achieve the best control and driving state, known as the vehicle four-wheel positioning.
What are the contents of four-wheel positioning?
Simply put, four wheel positioning includes front wheel positioning Angle and rear wheel positioning Angle. In terms of expansion, the positioning Angle of the front wheel includes: front bundle Angle, camber Angle, kingpin back Angle, kingpin inner Angle, inclusion Angle and receding Angle. The rear wheel positioning Angle includes front beam Angle, camber Angle, receding Angle and thrust Angle. For riders, just remember that the only things that can be adjusted are the front beam and camber, and the rest can be monitored. So how are the angles defined and what are their functions?
The definition of front beam Angle refers to the Angle between the left and right wheel rotation plane and the thrust line respectively called the front beam of two wheels, its function is to reduce tire wear and maintain straight driving.
Camber is defined as the Angle at which the top edge of the tire leans inwards (towards the engine) or outwards (away from the engine) of the vehicle. Its function is to be able to adjust the vehicle load acting on the center of the tire, eliminate deviation, thereby reducing tire wear.
What can cause changes in four-wheel positioning?
In general, when the vehicle encounters the impact of external overload, problems such as deformation of bearing structural parts and failure of bolt fastening system will occur, and the four-wheel positioning parameters set at the factory will also change, resulting in abnormal driving of the vehicle. The following scenes in daily life will lead to changes in four-wheel positioning. You can check to see if you have the following experience.
The vehicle was driving on the bumpy road for a long time.
Vehicle rear-end collision, impact and other traffic accidents, resulting in chassis parts deformation.
After a long time of use, rubber bushing wear, spring deformation and other problems.
Vehicles often cross rails and curb at high speed, resulting in deformation of chassis parts.
The chassis parts of the vehicle have not been restored to the factory parameters after replacement and maintenance.
What problems will occur when four wheel positioning is abnormal?
Abnormal four-wheel positioning will generally appear eating tires, deviating and abnormal direction, as well as heavy steering, floating and other three aspects of the fault phenomenon. We analyze the specific manifestations and causes of each fault one by one:
1. The phenomenon of eating fetus and the causes of formation
Tire outer edge wear, too much camber or suspension wear.
Tire inner edge wear, too little camber or suspension wear.
Tire outer edge feather wear, tire outer edge wear fast, the front bundle Angle is too large to form the inner eight.
The inner edge of the tire is feathered, the inner edge of the tire is worn rapidly, and the front beam Angle is negative to form the outer slab-shaped.
Block tire wear: static wheel imbalance or poor rear wheel front bundle.
2. Reasons for the formation of deviation phenomenon
The rear Angle of the front wheel kingpin is asymmetrical, with a deviation of more than 0.5 degrees. The vehicle deviates to the side with the smaller rear Angle of the kingpin.
The front wheel camber Angle is asymmetrical, with a deviation of more than 0.5 degrees. The vehicle deviates from the side with the larger positive camber of the front wheels.
Rear wheel camber is asymmetrical, deviation is more than 0.5 degrees. The vehicle deviated to the side with the lower Angle of the rear wheel.
Due to the change of the distance between the front and rear axles of the vehicle, the difference of the Angle of retreat is more than 0.2 degrees, and the vehicle runs off to the side with the small wheelbase.
3, the direction of the disc sink or steering wheel floating causes
Kingpin rear Angle is too large.
The camber Angle is not correct, and it inclines inwards.
The front beam Angle forms an inner or outer splay (the cause of steering wheel drift).
Through the above analysis, it is not difficult to see that four-wheel positioning is still very important for the owner, then, how long or what situation needs four-wheel positioning detection? The following eight types of four-wheel positioning need to be done for your reference:
1. The vehicle is driven every 10,000 kilometers or after six months.
2. Pull the car to the left or right when going straight.
3, the need to grip the steering wheel when driving straight, have the feeling of beater.
4. Feel the body float or wobble.
5, front or rear wheel single wheel wear.
6. After maintenance of collision accident.
7, change the new suspension or turn to the relevant accessories.
8. After the new car has been driven for 3000 kilometers, the run-in of all parts of the vehicle is completed, and it is best to correct through four-wheel positioning.
Keeping the vehicle in the normal four-wheel positioning value can increase driving safety, maintain straight line driving, improve the sense of driving control, reduce fuel consumption and tire wear, reduce the loss of suspension parts. In most cases, 80% of the problems with the four-wheel positioning of our vehicles are caused by our own bad driving habits. It is important to develop good driving habits and regularly check the four-wheel positioning of vehicles. Finally, I hope you will not be confused, do not do positioning, what situation to do positioning, according to this post you can fit in.