The axle shaft, also known as the drive axle assembly or half shaft, transmits torque from the differential to the drive wheel. When this critical component fails, you may notice clicking or clunking sounds during turns, grease leakage from damaged CV boots, vibration at higher speeds, excessive play in joints or bearings, or even complete loss of drive in severe cases. Regular inspection of CV boots and seals is essential for early detection. During service, always check splines and hubs for wear or deformation, follow precise torque specifications for hub nuts and flange bolts, ensure correct orientation during installation to prevent binding, and avoid impacts to bearing or splined ends to maintain proper function.