When one of the vehicle's four wheel bearings is damaged, you hear a continuous hum in the car while driving, which can't tell where it comes from, and feel the whole car is full of this hum, and the faster the speed is the louder the sound.
Here's how to judge:
Method 1: Open the window to listen to whether the sound comes from outside the car;
Method two: after raising the speed (when the hum is large) will be positioned in the neutral to let the vehicle taxi, observe whether the noise is coming from the engine, if the hum sound does not change when the blank taxiing, it is mostly the wheel bearing problem;
Method three: temporary parking, get off to check the temperature of the axle is normal, the method is: touch the four wheels by hand, roughly feel whether their temperature is consistent (brake shoes, chip clearance is normal, the temperature of the front and rear wheels is a gap, the front wheel to high), if the difference is not big to continue slow driving to the maintenance station;
Method four: with the lift will be raised the car (before loosening the handbrake, hanging blank), no lift can use the jack one by one raise the wheels, manpower quickly turn four wheels, when encountering the problem axle, it will make a sound, and other axles are completely different, with this method can easily tell which axle has a problem. If there is serious damage to the hub bearing, it must be replaced with cracks, hemp points or ablation. Before installing new bearings, grease, and then in reverse order, the replaced bearings must be rotated flexible and free of clutter and vibration.