A car's engine cannot power all of the wheels alone. That’s why the drive shaft is necessary to propel the vehicle. To propel the drive wheels it is necessary to take power from engine and send it to drive wheels by means of a drive shaft (half shaft). As it is transmitting the torque from the engine to the wheels, the drive shafts are subjected to the torsional stress and shear stress, which cause the failure of drive shaft. Any break down in drive shaft will cut the power flow from engine to the drive wheels. That’s why it is indispensable to analysis the drive shaft. The properties required to the drive shaft are hardness on the surface to resist the wear and toughness in the core to resist the deformation that can be achieved by doing the heat treatment.