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A clutch is a mechanical device which engages and disengages power transmission especially from driving shaft to driven shaft.
Double clutching is a method of shifting gears used primarily for vehicles with an unsynchronized manual transmission, such as commercial trucks and specialty vehicles. While double clutching is not necessary in a vehicle that has a synchronized manual transmission, the technique can be advantageous for smoothly downshifting in order to accelerate, and when done correctly it prevents wear on the "synchros" which normally equalize transmission input and output speeds to allow downshifting.
An automatic transmission, also called auto, self-shifting transmission, n-speed automatic, or AT, is a type of motor vehicle transmission that can automatically change gear ratios as the vehicle moves, freeing the driver from having to shift gears manually. Like other transmission systems on vehicles, it allows an internal combustion engine, best suited to run at a relatively high rotational speed, to provide a range of speed and torque outputs necessary for vehicular travel. The number of forward gear ratios is often expressed for manual transmissions as well.
Overdrive is a term used to describe the operation of an automobile cruising at sustained speed with reduced engine revolutions per minute (RPM), leading to better fuel consumption, lower noise, and lower wear. Use of the term is confused, as it is applied to several different, but related, meanings.
A transmission is a machine in a power transmission system, which provides controlled application of the power. Often the term transmission refers simply to the gearbox that uses gears and gear trains to provide speed and torque conversions from a rotating power source to another device.
In mechanical or automotive engineering, a freewheel or overrunning clutch is a device in a transmission that disengages the driveshaft from the driven shaft when the driven shaft rotates faster than the driveshaft. An overdrive is sometimes mistakenly called a freewheel, but is otherwise unrelated.
A semi-automatic transmission is an automobile transmission that combines manual transmission and automatic transmission.
Manumatic, a portmanteau of the words manual and automatic, is a term referring to a class of automotive transmission.
Hydramatic is an automatic transmission developed by both General Motors' Cadillac and Oldsmobile divisions. Introduced in 1939 for the 1940 model year vehicles, the Hydramatic was the first mass-produced fully automatic transmission developed for passenger automobile use.
A direct-shift gearbox, commonly abbreviated to DSG, is an electronically controlled dual-clutch multiple-shaft manual gearbox in a transaxle design, without a conventional clutch pedal and with fully automatic or semi-manual control. The first actual dual-clutch transmissions were derived from Porsche in-house development for their Model 962 racing cars in the 1980s.
A preselector or self-changing gearbox is a type of manual gearbox used on a variety of vehicles, most commonly in the 1930s. The defining characteristic of a preselector gearbox is that the manual shift lever is used to "pre-select" the next gear to be used, then a separate control is used to engage this in one single operation, without needing to work a manual clutch.
The F23 is a five-speed manual transmission manufactured by Getrag in Italy. It is designed for transverse engine applications, primarily by General Motors. It can handle torque inputs of over 230 newton metres (170 lbf⋅ft).
A transmission control unit or TCU is a device that controls modern electronic automatic transmissions. A TCU generally uses sensors from the vehicle as well as data provided by the engine control unit (ECU) to calculate how and when to change gears in the vehicle for optimum performance, fuel economy and shift quality.
A gear stick, gear lever, gearshift or shifter is a metal lever attached to the shift assembly in a manual transmission-equipped automobile and is used to change gears. In an automatic transmission-equipped vehicle, a similar device is known as a gear selector. A gear stick will normally be used to change gear whilst depressing the clutch pedal with the left foot to disengage the engine from the drivetrain and wheels. Automatic transmission vehicles, semi-automatic transmissions, and those with continuously variable transmission gearboxes do not require a clutch pedal.
A sequential manual transmission is a non-traditional type of manual transmission used on motorcycles and high-performance cars for auto racing, where gears are selected in order, and direct access to specific gears is not possible.
A non-synchronous transmission is a form of transmission based on gears that do not use synchronizing mechanisms. They are found primarily in various types of agricultural and commercial vehicles. Because the gear boxes are engineered without "cone and collar" synchronizing technology, the non-synchronous transmission type requires an understanding of gear range, torque, engine power, range selector, multi-functional clutch, and shifter functions. Engineered to pull tremendous loads, often equal to or exceeding 40 tons, some vehicles may also use a combination of transmissions for different mechanisms. An example would be a power take-off.
The GM MR6/F40 six-speed manual transaxle was first developed for Fiat, and use after by OPEL and Saab applications. Originally a design developed for Fiat, Opel and Saab applications, the F40 (MT2) is developed by GM Powertrain Sweden Södertälje - Europe six-speed manual transaxle built by Opel in Rüsselsheim am Main, Germany(2004-today). Its first use in a North American application was the Pontiac G6 for the 2006 model year. It is also used in Saab 9-3 2003-2011 and 9-5 2010-2012 models.
A motorcycle transmission is a transmission created specifically for motorcycle applications. They may also be found in use on other light vehicles such as motor tricycles and quadbikes, go-karts offroad buggies, auto rickshaws, mowers and other utility vehicles, microcars, and even some superlight racing cars.
A layshaft is an intermediate shaft within a gearbox that carries gears, but does not transfer the primary drive of the gearbox either in or out of the gearbox. Layshafts are best known through their use in car gearboxes, where they were a ubiquitous part of the rear-wheel drive layout. With the shift to front-wheel drive, the use of layshafts is now rarer.
Car controls are the components in automobiles and other powered road vehicles, such as trucks and buses, used for driving and parking.