Period 1  Auto Electrical Systems 120 -  Chapter 3 Sockets, wrenches Period 2  Powertrain & Chassis 110 - Chapter 3  Wrench sizes/ Measurements (remember to measure!!) Period 4  Internal Combustion Engines 110 -  Chapter 3 Wrench sizes/ Measurements (remember to measure!!) Period 6  Internal Combustion Engines 110 - Chapter 3  Wrench sizes/ Measurements (remember to measure!!)