What are the causes of cracks in a car's drive shaft?

[BellaAnn]

The causes of cracks in a car's drive shaft are: 1. The dynamic balance of the drive shaft assembly exceeds standard specifications; 2. Deformation of the drive shaft, detachment of balance patches, or asymmetry of bearing cover balance shims; 3. Loosening or damage of drive shaft connecting bolts; 4. Improper assembly of the drive shaft, such as the four flange bolts not being tightened to the specified torque or a screw thread being stripped, lack of grease or improper lubrication in the universal joint bearings; 5. Failure to strictly adhere to repair process procedures during maintenance operations, resulting in deformation of drive shaft components due to random hammering; 6. Improper driving operations causing impact damage to the drive shaft components; 7. Deformation of the support bracket, altering the perpendicular position between the drive shaft and rear axle axis, leading to the twisting off of the rear flange mounting bolts and subsequent detachment of the drive shaft.