Just like the engine, the transmission plays a vital role in the operation of the average vehicle. The transmission helps convert the power and torque provided by the engine into usable forward motion that is transferred to the drive wheels through a driveshaft or a set of half-shafts. The average transmission features a set of forward gear ratios that multiply the amount of force transmitted from the engine. As the vehicle moves forward, the transmission uses progressively taller gears to help the vehicle move faster. Without the transmission, the average vehicle would not be able to travel efficiently at high speeds.
Nearly all vehicles come with one of two types of transmissions automatic or manual. The number of gears used in a transmission depends on the type of vehicle and its intended application. Five-speed manual transmissions were once the norm, while six-speed transmissions were reserved for high-performance vehicles. Most automatic transmissions had to make do with four forward gears and an overdrive ratio until recently, when five-speed automatic transmissions became available. With ever-increasing advances in technology and the growing need for fuel efficiency, six-speed manual and automatic transmissions are becoming commonplace in most mainstream cars.
The difference between a five-speed and a six-speed car is simple: cars that utilize six-speed transmissions have the advantage of an extra gear ratio. This means that the engine can remain within its optimal power band under high-performance situations, drastically improving performance. The extra gear also helps the engine operate at a lower RPM at cruising speeds, thereby lowering fuel consumption. This difference is most noticeable at highway speeds.
Six-speed manual transmissions come with an extra shift position, sometimes in place of the reverse position. Reverse is often relocated to the far left and up or, in other cases, to the far right and down. These positions depend on the transmissions manufacturer. In the case of a six-speed automatic, there are not often any visual differences, nor are there any differences perceived by drivers in ordinary driving. The only difference may be a lower RPM at cruising speeds and the ability to stay within the engines power band.
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What's the difference between a 5-speed and a 6-speed car