What items should I do for the maintenance of 20,000 kilometers of cars?

1, change the oil; 2. Replace the oil filter and fuel filter; 3. Replace the air filter; 4. Replace the air conditioner filter; 5. Check the spark plug; 6. Do four-wheel dynamic balance; 7. Check the brake pads. The functions of vehicle maintenance are: 1 to ensure that the vehicle is in a good performance state; 2. Effectively improve vehicle efficiency and reduce the consumption of spare parts and tires; 3. Increase driving safety; 4. Avoid vehicle failure; 5. Reduce noise and environmental pollution; 6. Keep the appearance of the vehicle clean and tidy to prevent the vehicle from being damaged.