The popularity of automatic transmissions has means many of today's drivers don't need to know anything about clutches or stick shifts, a far cry from the days where manual transmissions were the norm. Despite the prevalence of automatic transmissions, many drivers still opt for manual models. Not only are these cars frequently cheaper, but some drivers feel they offer a level of performance and engagement with the vehicle that automatics simply can't. Thus, drivers who learn how a manual transmission works - and how to operate a stick-shift vehicle - can learn a useful skill that may save them money in the long run.
The key to a transmission is right there in its name. Everyone knows an engine generates the power for a vehicle to move - but how is that energy transferred into turning the wheels? The job of any transmission is to "transmit" that power from the engine to the wheels of the vehicle.
However, it gets much more complex than that. Not only is the transmission responsible for sending that power from the engine to the vehicles, but it also needs to regulate it. All engines have what's known as a "redline." This is the limit on how many rotations per minute (RPMs) the engine can handle safely. On both manual and automatic vehicles, drivers can watch their RPMs using a gauge on the dashboard. However, on automatic cars it's mainly there for show - the car will shift gears automatically to prevent a redline from occurring. Manual transmission drivers need to watch this meter carefully so that they know when to shift gears.
Depending on the engine, different amounts of horsepower and torque will be delivered in different RPM ranges. The problem is that driver's wishes don't always line up with the RPMs that a car is delivering. A driver might need to slow down, but the RPMs are too high. This is where the transmission comes into play - it delivers the power to the wheels in such a way that the car remains under control. This also allows a driver to take advantage of the RPM ranges where their engine delivers the most horsepower and torque.
The transmission accomplishes this the same way in both vehicles - by a series of gears in the transmission. When a driver hears the term "shift gears," this isn't simply a turn of phrase. There are actual gears with teeth in the transmission that affect how the car is driven. When a manual driver moves the shifter in the vehicle, they are causing different sets of gears to link up with each other, and in turn affecting the amount of power being transmitted to the wheels. An automatic car handles all of this using just one set of gears, but those who know a little about cars tend to prefer manual transmissions because it gives them more flexibility when it comes to handling the car's power.
Drivers with a manual transmission also need to learn how to use the clutch. This part of the vehicle is in place to prevent something very bad from happening. While an engine is turned on, it's constantly spinning and generating power. As stated before, the transmission needs to regulate that power - and this includes slowing down. The engine needs to be connected to the wheels in order for the vehicle to move, but it needs to be disconnected from the wheels if it's ever going to slow down. This is the job of the clutch - when pressed down, the transmission will disengage from the engine and the car can slow down, as it's not receiving any power. Again, this is something that's regulated in an automatic vehicle, but manual drivers need to pay close attention.