subassemblies and wear parts to understand the advantage of the present invention it is important to appreciate the complexity of modern transmissions the transmission is probably a vehicle 39 s most complex system in terms of automotive mechanics transmission systems vary from one vehicle to another with a manual transmission sometimes called a standard transmission an operator shifts into the proper gear at the proper time in an automatic transmission on the other hand the shifting is performed by the transmission but the result is the same in either case the transmission transmits power from the engine and directs it to the wheels it is part of a system that has several components commonly known as the drive train tires must be told how fast to turn and they must be supplied with extra power for starting climbing hills and pulling heavy loads all these things are accomplished via the drive train when one steps on the accelerator the engine is compelled to produce power but that power has to get to the wheels in the proper way for the wheels to respond most efficiently there are ways to convey that extra power to the wheels by controlling how fast they turn in relation to the engine 39 s speed thus a transmission has more than just forward and.