Gear Oils

Gears are mechanical device, comprising of toothed wheels used to transmit power from one shaft to another, placed in the same-direction or at an angle to each other at a speed which may be equal higher or lower.
The high engine speed has to be slowed down to the actual speed required by the road wheels. This is done at the gear box at the final drive. A gear receives the power from the one part of machine and transfers it to the another part. In automobiles, they are used to :
1. Change shaft speed.
2. Change the direction of rotation (reversing)
3. Change the amount of torque available at the wheels

The use of these gears dependent on the purpose for which it is required. A simple step up or a step down operation could be transmitted through a spur gear, whereas the similar operation at a much higher load may necessitate a helical gear where the contact area between the teeth and of the two gears being more. It
is capable of with standing greater loads.