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{{Short description|Lever used for shifting gears manually}}
[[File:Peugeot 206 1999 Hatchback 1.1 TU1JP(HFZ) 02.JPG
[[File:15-08-Schaltknauf-Kenworth-IMG 1723.JPG|thumb|Gear shifter for a 10-speed [[Eaton Corporation|Eaton-Fuller]] Roadranger [[Non-synchronous transmission|crash gearbox]]]]▼
A '''gear stick''' (rarely spelled ''gearstick''),<ref>{{cite web|url=http://www.oxforddictionaries.com/us/definition/american_english/gear-lever|archive-url=https://web.archive.org/web/20150412155351/http://www.oxforddictionaries.com/us/definition/american_english/gear-lever|url-status=dead|archive-date=April 12, 2015|title=gear lever
==Alternative positions==
[[File:Mercedes-Benz W 120 (180 D I) 07.01.21 JM (8).jpg
[[Image:Column shift.JPG|thumb|Column shifter for an automatic transmission in a [[Ford Crown Victoria]]]]
▲[[File:Mercedes-Benz W 120 (180 D I) 07.01.21 JM (8).jpg|left|thumb|Steering wheel with column-mounted gear lever in a [[Mercedes-Benz W120|W 120-series]] Mercedes-Benz 180]]
Gear sticks are most commonly found between the front seats of the vehicle, either on the [[Center console (automobile)|center console]] (sometimes even quite far up on the [[dashboard]]), the transmission tunnel (erroneously called a console shifter when the floor shifter mechanism is bolted to the transmission tunnel with the center console to cover up the shifter assembly when used with a rear or front-wheel drive vehicle), or directly on the floor. Some vehicles have a [[Manual transmission#
In some modern [[sports car]]s, the gear lever has been replaced entirely by "paddles", which are a pair of levers, usually operating electrical switches (rather than a mechanical connection to the gearbox), mounted on either side of the steering column, where one increments the gears up, and the other down. Formula 1 cars used to hide the gear stick behind the steering wheel within the nose bodywork before the modern practice of mounting the "paddles" on the (removable) steering wheel itself.
==
▲[[File:15-08-Schaltknauf-Kenworth-IMG 1723.JPG|thumb|left|Gear shifter for a 10-speed [[Eaton Corporation|Eaton-Fuller]] Roadranger [[
▲[[File:Peugeot 206 1999 Hatchback 1.1 TU1JP(HFZ) 02.JPG|left|thumb|A knob showing the driver the position of each gear]]
A knob, variously called gear knob, shift knob, gear shift knob or stick shift knob, forms the handle for the gear stick. Typically the gear knob includes a diagram of the ''shift pattern'' of the gear selection system, i.e. the positions to which the gear stick should be moved when selecting a gear. In some older manual transmission vehicles, the knob may incorporate a switch to engage an [[Overdrive (mechanics)|overdrive]]; in some automatic transmission vehicles it may incorporate a switch to engage a special mode such as a sports mode or to disengage overdrive. Both of the above-mentioned switches may also be found on the console or on steering column stalks instead. Manual shifters on the steering column, if having only three forward speeds, are typically called a
Starting the car in gear with the clutch engaged causes it to lurch forwards or backward since the starter motor by itself produces sufficient torque to move the whole vehicle; this can be highly dangerous, especially if the parking brake is not firmly applied and can be injurious to the starter and drivetrain. Therefore, novice drivers are taught to rock the knob of a manual gearbox from side to side before starting the engine to confirm that the gearbox is in neutral. For the same reason, modern cars require the clutch pedal to be depressed before the starter will engage (though some modern vehicles have a button that disables the clutch start requirement if held down when starting, for rare situations when starting the car in gear is necessary). The latter practice is also useful in extremely cold conditions or with a weak battery, as it avoids the starter motor also having to turn over a gearbox full of cold and highly viscous oil.
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==Secondary gear levers==
==Shift pattern==
[[
The shift pattern refers to the layout of the gears. In a typical manual transmission car, first gear is located to the left, and forwards. In many trucks and some sports cars it is instead in a "dog leg" position, to the left and rearwards. There is usually a spring-loading to return the stick to the central position. Reverse gear is commonly positioned in the best choice of location to avoid accidental engagement.
===Manual transmission===
[[File:RollsRoyceGearStick.jpg|thumb|Gear stick of [[Rolls-Royce Phantom I]] Open Tourer Windovers (1926)]]
[[File:
[[File:FIAT 500L gear shift.jpg|thumb|6-speed manual gear shift in a [[Fiat 500L]]]]
A typical manual transmission vehicle, with (for example) five forward gears, will thus have seven possible positions: the five forwards gears, reverse gear, and a central "neutral" position. Some vehicles have a special button to prevent accidental engagement of reverse. Others require that the lever be lifted (e.g. [[Nissan]]), pressed down (e.g. [[Volkswagen]]), or moved with extra force (e.g. [[BMW]]) to engage reverse. In transmissions with reverse directly below fifth, there may be a mechanical lock-out preventing selection of reverse other than from neutral, thus preventing a driver used to a six-speed transmission from engaging reverse while trying to select sixth. Some transmissions also have an electronically controlled [[pokayoke|error-prevention safeguard]] that blocks the first and sometimes the second gear from being selected if the vehicle is moving fast enough to exceed the engine's maximum RPM.
{| class="wikitable"
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! Description
|-
| [[File:Manual Layout.svg|125px]]
| This shift pattern is the most common five-speed shift pattern. This layout is reasonably intuitive because it starts at the upper left and works left to right, top to bottom, with reverse at the end of the sequence and toward the rear of the car.
|-
| [[File:Manual Layout 2.svg|125px]]
| This shift pattern is another five-speed shift pattern which can be found in [[Saab Automobile|Saabs]], [[BMW|BMWs]], some [[Audi|Audis]], [[Eagle (
▲This shift pattern is another five-speed shift pattern which can be found in [[Saab Automobile|Saabs]], [[BMW|BMWs]], some [[Audi|Audis]], [[Eagle (disambiguation)]], [[Volvo Cars|Volvos]], [[Volkswagen|Volkswagens]], [[Škoda Auto|Škodas]], [[Opel|Opels]], [[Hyundai Motor Company|Hyundais]], most [[Renault|Renaults]], some diesel [[Ford|Fords]], most [[Holden]]/[[Vauxhall Motors|Vauxhalls]] and more. The selection of the reverse gear is to prevent the reverse gear from being selected accidentally while the vehicle is in motion, causing catastrophic damage to the transmission.
|-
| [[File:Manual Dogleg.svg|125px]]
| This shift pattern, sometimes called a [[
This gear pattern can also be found on some heavy vehicles{{snd}} such as lorries and tractors{{snd}} in which first gear is an extra-low ratio for use in extreme standing-start conditions, and would see little use in normal driving.
|-
| [[File:Manual Layout6.svg|125px]]
| This shift pattern is a typical pattern for a six-speed transmission. Six speeds is the maximum usually seen in single range transmissions, however many semi-trucks and other large commercial vehicles have manual transmissions with 8, 16 or even 20 speeds, which is made possible due to multi-range gearboxes. In such a case, Reverse is placed outside of the "H," with a canted shift path, to prevent the shift lever from intruding too far into the driver's space (in [[driving on the left or right|left-hand drive]] cars) when reverse is selected. Higher number of speeds in automobiles are rare occurrences, although examples do exist, such as the [[Porsche
|-
| [[File:Manual Layout4d.svg|125px]]
| Shift pattern for a 4-speed car. Also found in column shift (Citroën DS/ID and Peugeot 404 from September 1967 onwards). In some British vehicles, namely the Triumph Herald, reverse is on the opposite side (left-left-up not right-down).
|-
| [[File:Manual Layout 3.svg|125px]]
| Shift pattern for a 3-speed car.
|-
| [[File:Column4MT.svg|125px]]
| Shift pattern for a 4-speed column shifter. Found like this in Peugeot 403 and 404 until September 1967.
|}
===Automatic transmission===
Automatic transmissions traditionally have had a straight pattern, adopting the classic ''P-R-N-D gate'', with "P" being to the front, topmost position (or "P" all the way to the left on a column-mounted shifter); the corresponding shift positions being:
* P = Park
* R = Reverse
* N = Neutral
* D = Drive
All automatics use some sort of manual override of the transmission, with numbered positions in descending order marked below (or to the right) of "drive", which will prevent the transmission shifting to a gear higher than the selected, but maintaining automatic operation between all lesser numbered gears. Such gates will appear as ''P-R-N-D-3-2-1'' for example. On some vehicles (mainly Japanese makes such as [[Honda]], [[Toyota]] and [[Lexus]]) these numbered positions are replaced by a single "L" (for "low") position, which will hold the transmission in whatever lower ratio is required for climbing steep grades or for heavy acceleration: ''P-R-N-D-L''.
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More modern automatic transmissions have employed a "J-gate" (pioneered by [[Jaguar (car)|Jaguar]]) where some gears are on the left-hand "arm", some on the right, and there is a sideways movement at the rear of the pattern. The second-generation [[Range Rover]] from 1995 used an "H-gate", with two parallel PRND gates on the opposing legs of the "H" for both high range and low range ratios, for normal and off-road driving, respectively.
==Electronic gear shifts==
[[File:2010 Jaguar XF (X250) sedan (2010-10-16).jpg|right
With the advent of [[drive by wire]] (or more properly, [[shift by wire]]) computer-controlled transmissions (particularly in the case of automatics), the gear stick no longer needs to be mechanically connected to the transmission unit itself, and can, therefore, be made much smaller since there is no need to package either remote mechanisms or complex interlocking arrangements. This has allowed designers to replace the gear stick completely with either button, rotary knobs (current [[Jaguar Cars|Jaguar]], [[Land Rover]] and [[Ford Motor Company|Ford]] models are good examples of this), or a miniaturized gear stick on the center console. This can be seen in some [[Audi]]s, [[BMW]]s and the [[Lincoln Continental#Tenth generation (
==Special knobs==
A ''shift knob'' also known as a ''gear knob'', ''gear shift knob'' and ''stick shift knob'' is the physical interface between the
The shift knob's principal function is the [[ergonomical]] interface between driver and the
In recent years, manufacturers have increased the variety of shifts knobs available to the consumer from inexpensive plastics to diamond-studded white gold.<ref>Yamamoto, Mike. (2007-03-06) [http://news.cnet.com/8301-17938_105-9694174-1.html The $150,000 shift knob] {{Webarchive|url=https://web.archive.org/web/20121025011426/http://news.cnet.com/8301-17938_105-9694174-1.html |date=2012-10-25 }}. News.cnet.com. Retrieved on 2011-06-13.</ref>
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==
* [[List of auto parts]]
== References ==
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