The transmission of a vehicle controls the gear-ratio between the engine output and what is sent to the rest of the drive system. As you move to higher gears your torque decreases, but your drive speed increases relative to you engine output speed. There are three types of transmissions to consider, each with their own advantages and disadvantages.
There are several basic types of transmission, all with their own advantages and disadvantages.
- Manual Transmissions are the oldest type. They are simpler and generally considered to be tougher, although there are many exceptions to this rule. Manual transmissions generally have more gears available giving you greater range or torque, top-speed, and fuel efficiency. They allow for greater performance as they do not take power from the engine to operate, but they do require one to be relatively good at using them to reap these benefits.
- Automatic Transmissions change gears for you, freeing up an extra hand and requiring less effort on the part of the drive. Many people today do not know how to drive a manual, making an automatic their only option. Automatic transmissions do take some power from the engine to operate, degrading performance.
- Continuously Variable Transmissions are a very new type of transmission with many different proprietary implementations. What they all have in common is a lack of discrete gearing. This means that they never have to disengage power from the drive system while they dynamically increase and decrease gear-ratios. This gives them a huge advantage in fuel efficiency and acceleration. The downside is that they are so new no one knows for sure how durable they will be.