The chassis is the basis of the overall design of the vehicle, providing driving, steering and braking forces for the use of the vehicle, and ensuring the normal driving of the vehicle. The chassis is also an important part of the vehicle maintenance work, especially for the car owners who have not undergone rust prevention treatment.

In terms of structure, the vehicle chassis is mainly divided into four systems:

1. Transmission system: mainly including clutch, transmission, universal transmission, final drive, differential and half shaft.

2. Driving system: axle, frame, suspension, wheel, etc.

3. Steering system: steering wheel, steering shaft, steering column, etc.

4. Braking system: mainly composed of energy supply device, control device, transmission device and brake.

Normal maintenance needs to start from the above four systems:

1. Drive system

For transmission system maintenance, first check the transmission oil tank, check the oil quality and level. If there is any change, it needs to be replaced or added in time.

Note that the transmission bearing also needs to be added with lubricating oil.

During maintenance, check whether the dust boot is damaged. If it is damaged, replace it in time.

Check the oil quality and oil level of the reducer, add and replace it appropriately, and keep it in a closed state to avoid oil leakage.

During the seasonal maintenance, especially in winter and summer, the use of oil is different. Pay special attention to the oil concentration. In general, the viscosity of the oil will change with the temperature. In winter, try to choose the oil with lower viscosity, and in summer, choose the oil with higher viscosity, so that the engine can be used more smoothly.

It is worth noting that when refueling the vehicle in winter and summer, the oil volume also needs to be controlled. When the engine oil warning lamp or engine oil pressure gauge is on, you should find a suitable location to stop and check the oil volume. If the oil volume is insufficient, you need to add it in time. Pay attention to add the correct engine oil according to the model of the car, and do not mix it to avoid carbon deposition due to a large amount of mixed liquid left in the steam tank.

2. Travel system

It is necessary to check whether the tightness of the wheel hub bearing is appropriate, whether the front wheel positioning is accurate, and whether the tire pressure meets the standard.

The wheel hub bearing is too tight, which will increase the friction of wheel rotation; If it is too loose, the wheels are prone to skew or swing during driving. It is recommended that car owners regularly check and adjust the tightness of the wheel hub in a professional repair shop to maintain the best condition of the wheel rim.

The front wheel alignment can ensure that the wheels are in a pure rolling state when the vehicle is driving, and maintain the vehicle's driving stability and steering portability. If the front wheel alignment is not accurate, it is easy to cause the front wheel to roll in a sliding manner during vehicle use, improve wheel wear, increase the friction resistance between the vehicle and the ground when the vehicle is driving, and lead to poor sliding performance and increased fuel consumption. The car owner can go to a professional repair shop for four-wheel positioning at ordinary times.

The tyre pressure should be adjusted in time according to the weather and road conditions.

3. Steering system

The steering fluid is often in the working environment of continuous extreme pressure and high temperature, which is prone to pollution degradation and loss of lubrication performance, and the formation of paint film and other deposits, resulting in difficult vehicle steering, steering wheel shaking, etc. If the sediment cannot be removed regularly, it is very easy to damage the hydraulic oil pump in the system, resulting in high maintenance costs.

The maintenance of the steering system mainly includes the following points:

Slow down when driving on the potholed road to reduce the load borne by the steering gear;

Check the status of the dust shield once a month. If the shield is damaged, it must be replaced immediately, and the steering gear should be checked and maintained comprehensively before replacement;

After four-wheel alignment and toe in adjustment and steering rod replacement, special attention shall be paid to the protection sleeve to avoid distortion, improper assembly, etc., otherwise the protection sleeve may be damaged;

Every 100000 km or so, the steering gear shall be fully maintained, cleaned and re greased;

The steering gear has poor service conditions and large load, so special grease must be used, and ordinary grease cannot meet the requirements;

The clearance of the steering gear will gradually increase when it is used. If the left and right idle stroke of the steering wheel exceeds 15 degrees, the steering gear must be checked. If the gear rack is abnormally worn, the steering gear assembly must be replaced. If there is no abnormal wear, but the clearance is too large, it can be adjusted.

4. Brake system

Good braking performance is the guarantee of safe driving. If the vehicle is found to have brake deviation or brake effectiveness decline, it must be repaired or replaced at the maintenance point in time. For the sake of safety, it is better to test the brake in advance before driving at ordinary times to ensure that there is no abnormality before starting.

How to maintain the brake system when the weather is getting colder?

In winter, the temperature is low, and the sealing ring or cushion is hard, which is easy to cause the contraction of the sealing pipe joint. Before driving, check the sealing of each joint of the air circuit, and it is better to touch it one by one, tighten it or reinstall it in time.

Check the main vehicle dryer tank to ensure that the main vehicle air source is dry and free of moisture.

In winter, the temperature is mostly below zero, and the gas is easy to produce water droplets. Therefore, the main vehicle and trailer air reservoirs need to drain water regularly to ensure dry gas for braking. If the water is not drained in time, the moist gas in the air reservoir is easy to enter the valve body. When the temperature is lower than zero, ice will form, which will cause the piston to lock and affect the braking performance.

When ABS connects multiple sensor connectors, check and maintain all sensor connectors. At the same time, the ABS gear ring shall be removed and cleaned regularly to ensure that the sensing signals of the gear ring and the probe are good and the connector is free of putty.

In order to ensure the stable braking performance of the trailer, in addition to the routine maintenance of the braking system, it is also very important to select an axle with good quality and stable performance. The higher the quality of the axle, the more sensitive and reliable its braking performance, which can guarantee the driving safety in severe cold weather.