The purpose of the vehicle drive shaft is to transfer torque from the transmission to the differential, which then transmits the torque to the wheels for moving the vehicle. The car drive shafts are subject to torsional and shear stresses and they must be strong enough to withstand the pressure. For the drive shaft for cars and trucks, the damaged casing must be replaced immediately to prevent damage to the joint due to dirt penetration or grease escaping. The car can use the vehicle drive shaft to transfer power from the engine to the other end of the vehicle before the engine reaches the wheel. They are typically used to transfer power from the center differential, transmission or transaxle to the wheels.