The difference between routine maintenance and primary and secondary maintenance of automobiles.

The first-class maintenance is generally carried out when the vehicle travels to 1500~2000km. It focuses on fastening and lubrication. The main contents are: check and tighten the loose bolts and nuts in the exposed parts of the car, add grease and lubricating oil to each assembly according to the lubricating performance, and clean each filter.

Secondary maintenance is generally carried out when the car is driving 6000~8000km. The secondary maintenance centers on inspection and adjustment, and carries out more in-depth inspection and adjustment on the technical condition of vehicles that have traveled for a certain mileage, with the aim of keeping the vehicles in good driving performance for a long time in the future. There is a lot of work in secondary maintenance. In addition to all the work in primary maintenance, some faults and hidden dangers found in maintenance work must also be eliminated. Maintenance takes a long time and is usually carried out by maintenance workers.