The mileage is about 60 thousand km, and the model is E70, the BMW X5 sport utility vehicle equipped with N55 engine in 2012. The user reflects: the chassis has a different sound when the car turns. Inspection and analysis: maintenance personnel commissioning confirmation, abnormal sound from the front axle. Check the chassis without any damaged parts. The car is a four-wheel drive, and the front axle is abnormal when it turns, indicating that it is related to the front wheel drive system. In order to isolate the fault, the fuse of the control unit of the distributor is removed, so that the torque distribution before and after is 0:100, that is, the rear wheel is used to drive the vehicle. Disconnect the front wheel drive and test the car, and the trouble will disappear. After inserting the fuse, repeated trial run confirms that the abnormal sound comes from the inner part of the distributor. Troubleshooting: after replacing the distributor assembly, test run and confirm troubleshooting.