TRANSMISSION

WHY NEED THE TRANSMISSION ?
A vehicle requires a lot of torque to start off and to climb hills, yet it does not require as much torque to move on level ground. Torque is a twisting or turning force that is exerted on the input shaft of a transmission/transaxle.

An engine produces increasing torque as its speed increases up to a certain point where the torque output starts to decrease. To get a vehicle moving or to accelerate up a hill, it is desirable to use a transmission that allows the engine speed to be increased even though the vehicle speed may be low.

Using gears allows the engine speed to increase at low vehicle speeds yet still permits it to drop at higher speeds to save fuel and reduce emissions.



What is a "Transmission"?
The transmission is a device that is connected to the back of the engine and sends the power from the engine to the drive wheels. An automobile engine runs at its best at a certain RPM (Revolutions Per Minute) range and it is the transmission's job to make sure that the power is delivered to the wheels while keeping the engine within that range. It does this through various gear combinations. In first gear, the engine turns much faster in relation to the drive wheels, while in high gear the engine is loafing even though the car may be going in excess of 70 MPH. In addition to the various forward gears, a transmission also has a neutral position which disconnects the engine from the drive wheels, and reverse, which causes the drive wheels to turn in the opposite direction allowing you to back up. Finally, there is the Park position. In this position, a latch mechanism (not unlike a deadbolt lock on a door) is inserted into a slot in the output shaft to lock the drive wheels and keep them from turning, thereby preventing the vehicle from rolling.