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50-418: The Dacia Easy-R is an automated manual transmission used by Renault and Dacia that uses electro-mechanical actuation (rather than electro-hydraulic actuation ) to automate the gear shifts. The Easy-R uses a traditional manual gearbox with a computer-controlled, electronic clutch ; the gear shifts are automatic, and the need for a clutch pedal is eliminated. The number of parts has been reduced by

100-443: A manumatic , the latter of which is an automatic transmission (automatics use a torque converter instead of a clutch like in an automated manual, to manage the mechanical linkage between the transmission and motor) with the ability to override the automatic transmission's computer, and actuate shifts manually. Add-on AMTs can also function as a regular manual gearbox (with a manual shift lever), whereas integrated AMTs do not need

150-422: A "normal" shift layout, so they can be designed with an optimized AMT shifting layout (which would have an unusual pattern to manually shift). Integrated AMTs either have gear-selector drums (which allows only serial shifting and no gear-skipping, but this system is fairly inexpensive, because it needs only one actuator), or single actuators. Single-actuator systems require one actuator for each shifting sleeve (which

200-419: 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

250-429: A conventional automatic transmission ), while traditional semi-automatic and clutchless manuals require the driver to manually select the gear even when the engine is at redline, since they automate only part of the transmission (namely the clutch), and will not shift gears by themselves. Despite the superficial similarity, automated manual transmissions differ significantly in internal operation and driver's "feel" from

300-471: A driver used to a six-speed transmission from engaging reverse while trying to select sixth. Some transmissions also have an electronically controlled 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. This gear pattern can also be found on some heavy vehicles – such as lorries and tractors – in which first gear

350-553: A quarter, ensuring better reliability and simplified maintenance. Easy-R was available in the Logan , Logan MCV , and Sandero models. It was also available in the Duster and currently it is still available in the Renault Kwid and Renault Triber . There are two versions: the 5-speed JS3 used in petrol engines and the 6-speed TS4 001 used in diesel engines. The Dacia Easy-R gearbox

400-424: A sequential mode, where the driver can upshift or downshift by only one gear at a time. However, this is not the case for all modern transmissions. For example, BMW's "SMG" and Ferrari's "F1" transmission can skip gears on both downshifts and upshifts, when selecting gears manually via the steering wheel-mounted paddle-shifters, as seen on most modern transmissions. Older clutchless manual transmissions (mostly prior to

450-478: 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 . More modern automatic transmissions have employed a "J-gate" (pioneered by 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

500-592: Is actually a manual gear lever connected to the gearbox with a linkage. In automatic transmission cars, the lever functions more like a gear selector, and, in modern cars, does not necessarily need to have a shifting linkage due to its shift-by-wire principle. It has the added benefit of allowing for a full width bench-type front seat (though some models with bucket seating as an option include it). It has since fallen out of favor, although it can still be found widely on North American-market pick-up trucks , vans, emergency vehicles (both law enforcement and EMS –

550-419: Is an extra-low ratio for use in extreme standing-start conditions, and would see little use in normal driving. 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: All automatics use some sort of manual override of

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600-611: Is another example. It is a revival of an approach used in the 1950s by the Chrysler push-button PowerFlite and the Packard Touchbutton Ultramatic . A shift knob also known as a gear knob , gear shift knob and stick shift knob is the physical interface between the gear stick and the driver's hand. Made of many materials from simple plastics through to platinum , it comes in many shapes sizes and weights. OEM shift knobs are generally spherical in shape, often resembling

650-404: 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. A typical manual transmission vehicle, with (for example) five forward gears, will thus have seven possible positions: the five forwards gears, reverse gear, and

700-467: 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 , Land Rover and Ford models are good examples of this), or a miniaturized gear stick on the center console. This can be seen in some Audis , BMWs and the Lincoln Continental . Japanese finger shift

750-720: Is notably favored over conventional automatic and CVT transmissions due to its lower cost. Automated manual transmissions can be semi-automatic or fully-automatic in operation. Several different systems to automate the clutch and/or shifting have been used over the years, but they will generally use one of the following methods of actuation for the clutch and/or shifting: hydraulic or electro-hydraulic actuation , electro-mechanical , pneumatic , electromagnetic , or even purely electrical using an electric motor . Gear shifting, clutch actuation, shift-timing, and rev-matching are all under automated control via electronic sensors, computers, and actuators. When shifting gears,

800-491: Is the 1955 Citroën DS , which used a 4-speed "BVH" transmission. This semi-automatic transmission used an automated clutch, which was actuated using hydraulics . Gear selection also used hydraulics, however, the gear ratio needs to be manually selected by the driver. The 1956 Renault Dauphine 3-speed manual transmission was available with an optional Ferlec automated clutch, which used an electromagnetically-operated clutch system. Other clutchless manual transmissions included

850-526: Is why this type of system is more expensive, but it also shifts faster). The actuators can either be electro-hydraulic (more expensive, but faster, well-suited for single-actuator systems, and allow for higher torque), or electro-mechanical (less expensive, but usually limited to 250 N·m (184.5 lb-ft ) of gearbox input torque). This limit is because the clutch actuation force increases with higher torque, and short shifting times; electro-mechanical actuators are just electric motors – using larger motors reduces

900-558: The E36 M3 coupe. Although the name "SMG" was an abbreviation of "Sequential Manual Gearbox", the transmission internal were as per a typical (synchromesh-equipped) manual transmission, not a true sequential manual transmission . The SMG was replaced by the SMG-II when the E46 M3 was introduced in 2000. BMW's final AMT (before being replaced by a dual-clutch transmission) was the 7-speed SMG-III used in

950-646: The clutch and/or shift gears . Many early versions of these transmissions that are semi-automatic in operation, such as Autostick , which automatically control only the clutch – often using various forms of clutch actuation , such as electro-mechanical , hydraulic , pneumatic , or vacuum actuation – but still require the driver's manual input and full control to initiate gear changes by hand. These systems that require manual shifting are also referred to as clutchless manual systems. Modern versions of these systems that are fully automatic in operation, such as Selespeed and Easytronic , can control both

1000-576: The "Shift-tronic" 6-speed semi-automatic was offered on the Alpina B12 coupe (based on the E31 850CSi). Using an automated clutch paired to a standard H-pattern shifter (as per the Ferrari Mondial T), the transmission was supplied by LuK and fitted to less than 40 cars. Mass-production of automated manual transmissions began for BMW in 1997 with the introduction of the "SMG" 6-speed automatic transmission in

1050-659: The 1940s and 1950s. An early example of this transmission was introduced with the Hudson Commodore in 1942, called Drive-Master . This unit was an early semi-automatic transmission , based on the design of a conventional manual transmission which used a servo-controlled vacuum-operated clutch system, with three different gear shifting modes, at the touch of a button; manual shifting and manual clutch operation (fully-manual), manual shifting with automated clutch operation (semi-automatic), and automatic shifting with automatic clutch operation (fully-automatic). Another early example

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1100-452: The 1967 NSU Ro 80 (3-speed Fichtel & Sachs ) and 1967 Porsche 911 (4-speed Sportomatic ), both of which used vacuum-actuated clutches and hydraulic torque converters. The 1968 Volkswagen Beetle and Volkswagen Karmann Ghia offered a 3-speed Autostick transmission, which used an electric switch on the gear shifter connected to a solenoid , to operate the electro-pneumatic vacuum clutch servo . In 1963, Renault switched from

1150-517: The 1990s) will retain H-pattern shifters, plus the shift gate, and will require the driver to select the required gear ratios manually. The clutch, however, will be a servo-controlled unit , connected to various actuators , a solenoid and sensors which control the clutch automatically. Another alternate means of clutch automation is the "clutch-by-wire" system. The system generally uses an electric actuator and electronic sensors , which replace

1200-440: The 2004-2010 BMW E60 M5 and related BMW E63 M6 . The SMG-III could achieve a shift time of 65 milliseconds in its most aggressive mode From 2002 to 2007, the third-generation Toyota MR2 was available with an "SMT" 6-speed automated manual transmission. The SMT system utilized an electro-hydraulic activation system for both the clutch and shifting, but no H-pattern shifter like with the standard transmission. Instead, there

1250-645: The Ferrari 458 in 2009. Sister company Alfa Romeo introduced the related Selespeed 5-speed automatic transmission for the Alfa Romeo 156 in 1999. This was followed by Maserati's 2001 introduction of the related Cambiocorsa 6-speed automatic transmission in the Maserati Coupé . Selespeed was also used in the Fiat Punto and Stilo models. BMW 's involvement with automated manual transmissions began in 1993, when

1300-467: The Japanese domestic market only). This transmission, originally designed for trucks, was based on a manual transmission with the addition of hydraulic actuators for the gear shifter and the clutch. Initial versions did not allow direct selection of gear ratios, instead allowing drivers only to lock out higher gears (as per many traditional automatic transmissions). Later versions added a manual mode, allowing

1350-444: The automated clutch to a fully-automatic 3-speed Jager transmission, which consisted of an electro-mechanical control unit that operated both the clutch and shifting, effectively making it one of the earliest automated manual transmissions. The Jager transmission was controlled via dash-mounted electronic push-buttons. The Isuzu NAVi5 5-speed automatic transmission was introduced in the 1984 Isuzu Aska mid-size sedan (sold in

1400-417: 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

1450-601: The clutch operation and the gear shifts automatically, by means of an ECU , therefore requiring no manual intervention or driver input for gear changes. The usage of modern computer-controlled AMTs in passenger cars increased during the mid-1990s, as a more sporting alternative to the traditional hydraulic automatic transmission. During the 2010s, AMTs were largely replaced by the increasingly widespread dual-clutch transmission , but remained popular for smaller cars in Europe and some developing markets , particularly India , where it

1500-469: The clutch, while the gearshift mechanism was a standard H-pattern shifter operated as per normal transmissions. In 1997, the Ferrari F355 became available with an "F1" 6-speed transmission, which uses paddle-shifters located behind the steering wheel or can be driven in a fully-automatic mode. The F355's successors offered similar transmissions, until the company switched to a dual-clutch transmission for

1550-706: The column shifter is retained where a floor shifter is unfeasible due to mounting the mobile data terminal and 2-way radio), and "full-size" US sedans such as the Ford Crown Victoria . A dashboard mounted shift was common on certain French models such as the Citroën 2CV and Renault 4 . Both the Bentley Mark VI and the Riley Pathfinder had their gear lever to the right of the right-hand drive driver's seat, alongside

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1600-403: The console or on steering column stalks instead. Manual shifters on the steering column, if having only three forward speeds, are typically called a three on the tree , and floor shifters having four forward speeds, are called four-on-the-floor . The lowest of these gears, if set at a much lower ratio than a typical 1st-gear ratio, is often called a granny gear . Starting the car in gear with

1650-437: The driver selects the desired gear with the transmission shift lever , while electronic sensors and actuators connected to a TCU (transmission computer) or microprocessor will automatically operate the clutch and throttle to match revs and to re-engage the clutch in milliseconds. Torque and power transfer to the drive wheels will also be electronically controlled. Most modern implementations of this transmission function are in

1700-579: The driver to control the gear selection. Several companies owned by Fiat S.p.A. were influential in the development of automated manual transmissions. Ferrari 's involvement with automated manual transmission began with the 7-speed semi-automatic paddle-shift transmission used in the 1989 Ferrari 640 Formula One racing car. In 1992, the Ferrari Mondial T introduced the option of a "Valeo" 5-speed semi-automatic transmission. This transmission used an electro-mechanical actuator to automatically operate

1750-420: The driver's door, where it was not unknown for British cars to also have their handbrake . ( Left-hand drive models received a column shift.) In some modern sports cars , 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

1800-420: 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 column shift where the lever is mounted on the steering column  – in vehicles with a manual four-speed gearbox such as 1950s Mercedes-Benz cars and all two-stroke Trabants , this

1850-412: 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 ; 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

1900-496: The gear stick. The Land Rover Freelander introduced a button for that company's Hill Descent Control system feature, which uses the brakes to simulate the function of a low-ratio gearbox in steep descents. Traditional four-wheel drive vehicles have one or more additional "shift levers" to engage a low-ratio gearbox (used on tough terrain ), a transfer case (which switches between two- and four-wheel drive), or differential locks. Some more modern traditional vehicles combine

1950-411: 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

2000-416: 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. 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

2050-425: The low-ratio gearbox and transfer case into one lever, with 3 positions: 2H (for 2-wheel drive in the standard high-ratio gearbox); 4H (for 4-wheel drive in the standard high-ratio gearbox); and 4L (for 4-wheel drive in the low-ratio gearbox). 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

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2100-399: The mechanical clutch linkage or hydraulic clutch connection, to monitor and control clutch positioning, completely replacing the hydraulic linkage between the mechanical clutch and pedal itself with a single electro-mechanical actuator. Depending on the mechanical build and design, some (mostly modern) automated manual transmissions will automatically shift gears at appropriate points (like

2150-768: The motor dynamics due to the motors' higher mass moment of inertia (which is not good for fast shifting), and bigger motors also put more stress on the car's 12-volt electrical system. As a result, one can have either slow shifting and a very large lead-acid battery (not suitable for cars), or fast shifting and a smaller battery (works up to 250 N·m of torque). Modern AMTs, such as Suzuki Auto Gear Shift and Dacia/Renault Easy-R , usually operate in conjunction with electronic throttle control to initiate gear shifts based on certain RPM and/or throttle position. The automated manual transmission has its origins in early clutchless manual transmissions that began to appear on mass-production cars in

2200-408: The opposing legs of the "H" for both high range and low range ratios, for normal and off-road driving, respectively. Most modern manumatics , such as Alfa Romeo 's Sportronic and Porsche 's Tiptronic , have a traditional automatic shift pattern on the left or right side of the gear selector, along with a connected longitudinal gate with "+" and "-" positions on the other side in which movement of

2250-475: The shifter forward and backward increments the gears up and down, respectively. This can be useful in snow or dirt conditions, where it may be necessary to start from second gear. 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

2300-489: The starter motor also having to turn over a gearbox full of cold and highly viscous oil. Many automatic transmission vehicles have extra controls on the gear stick, or very close by, which modify the choices made by the transmission system depending on engine and road speed, e.g. "sports" or "economy" modes which will broadly speaking allow, respectively, for higher and lower revolutions per minute, before shifting up. Some specialist vehicles have controls for other functions on

2350-432: 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

2400-416: Was a resounding failure, and now Dacia has switched to using CVT gearboxes on its new models. The Easy-R transmission has the following gears: R , N , D , M+ , M- Automated manual transmission The automated manual transmission ( AMT ) is a type of transmission for motor vehicles . It is essentially a conventional manual transmission equipped with automatic actuation to operate

2450-512: Was a shift lever that could be pulled and pushed forward or backward to upshift and downshift, as well as the addition of electronic steering-wheel-mounted shift buttons. Brands within the Volkswagen Group have typically used dual-clutch transmissions instead of automated manual transmissions, however a 6-speed "E-gear" automated manual transmission was introduced for the 2004 Lamborghini Murciélago . and Lamborghini Gallardo . The E-gear

2500-465: Was used on the successors to the Murciélago and Gallardo, and it was also available on the 2007-2012 Audi R8 (Type 42) , marketed as the "R-tronic" transmission. Gear stick Gear sticks are most commonly found between the front seats of the vehicle, either on the center console (sometimes even quite far up on the dashboard ), the transmission tunnel (erroneously called a console shifter when

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