Long term heavy load driving of heavy trucks, traveling in mountainous and mining areas, bumpy and muddy road conditions, etc., are prone to abnormal posture problems such as body tilting, driving deviation, front shaking, and left and right swaying of the body. Most drivers are accustomed to making do with driving and believe that it does not affect cargo operations and does not require maintenance, but in reality, vehicle attitude deviation is a hidden chassis fault. Long term neglect not only causes uneven tire wear, increased fuel consumption, and poor handling, but also exacerbates the uneven wear and tear of the suspension, axle, and braking systems, laying the foundation for driving safety hazards. Accurately identifying the causes of abnormal posture and scientifically adjusting the chassis condition are important maintenance methods for overseas fleets to low-cost correct vehicle conditions and extend the lifespan of the entire vehicle.
The imbalance between tires and tire pressure is the most common cause of abnormal driving posture. The uneven tire pressure and wear degree of coaxial tires in trucks can directly lead to uneven force distribution on the body, resulting in slight deviation and body tilting during driving. At the same time, foreign objects mixed in the tire tread, bulging deformation on one side of the tire, and slight deformation of the wheel rim can all disrupt driving balance. Under complex working conditions overseas, tire wear and tear differences are faster and easily overlooked in daily life. Most minor deviation faults can be quickly resolved through tire pressure calibration and tire rotation, without the need for complex repairs.
The aging and loosening of the suspension system is the core chassis cause of attitude deviation. The elastic attenuation, single piece fatigue deformation, and fracture misalignment of steel plate springs can cause uneven height on the left and right sides of the vehicle body; Aging and cracking of the balance shaft bushing and thrust rod rubber sleeve, as well as excessive clearance, can cause the axle positioning to shift, resulting in body shaking and unstable movement during driving. In addition, if the shock absorber leaks oil and fails, it will not be able to cushion the impact of road bumps, which will amplify the problem of vehicle sway and jumping. This type of malfunction belongs to progressive wear and tear, with mild initial symptoms. Long term neglect will completely disrupt the vehicle's driving posture and exacerbate overall premature aging of the chassis.
Loose chassis fasteners and parameter deviations can directly cause driving deviation. Long term bumps and vibrations can cause U-screws and suspension fixing bolts to loosen, resulting in steel plate displacement and axle displacement; At the same time, overloading and impact can change the parameters of the front toe and wheelbase, resulting in problems such as straight running deviation and steering wheel misalignment. After major repairs and disassembly of chassis components, some vehicles may experience abnormal posture without precise calibration, which continues to affect handling stability, increase driving fatigue and safety risks.
