4 to 7 years: middle age
　　At this time the car is like "people to middle age", a lot of things are loose, including a variety of rubber hose inside the car, car cover under the problem. Many car owners often in the car to four or five years when the car began to change, but also some used car buyers like to buy this car age car.
　　Rubber hose:
　　This car age of the car such as poor maintenance, leakage black oil, leakage problems will appear. This is very natural, rubber tube old, there will always be aging problems. If the owner of the car is well maintained, the problem of aging will be a little later.
　　Timing belt:
　　Drove the car of 4 years or so to want to pay attention to timing belt should be changed, average car drove 70 thousand to 100 thousand kilometers when, should send to change timing belt, if do not change in time, if timing belt breaks suddenly when the car runs halfway, the maintenance cost that should pay at least hundreds of yuan.
　　Tank:
　　5 years or so of the car, the water tank may be the inside of the chemical corrosion, some of the car's water tank began to leak, of course, the water tank needs to be replaced.
　　Replace your car's oil, filter, etc., on a regular basis.
　　This paper is sorted out by dongguan oneness filtration technology co., LTD.