Multitronic
Encyclopedia
multitronic is a stepless transmission
Transmission (mechanics)
A machine consists of a power source and a power transmission system, which provides controlled application of the power. Merriam-Webster defines transmission as: an assembly of parts including the speed-changing gears and the propeller shaft by which the power is transmitted from an engine to a...

 launched by AUDI AG
Audi
Audi AG is a German automobile manufacturer, from supermini to crossover SUVs in various body styles and price ranges that are marketed under the Audi brand , positioned as the premium brand within the Volkswagen Group....

 in late 1999, jointly developed and manufactured by LuK.

Based on the principles of continuously variable transmission
Continuously variable transmission
A continuously variable transmission is a transmission that can change steplessly through an infinite number of effective gear ratios between maximum and minimum values. This contrasts with other mechanical transmissions that offer a fixed number of gear ratios...

 (CVT) popularised by DAF
DAF Trucks
DAF Trucks NV is a Dutch truck manufacturing company and a division of PACCAR. Its headquarters and main plant are in Eindhoven. Cabs and axle assemblies are produced at its Westerlo plant in Belgium...

, multitronic offers a stepless automatic transmission in which the ratio between the input shaft and output shaft can be varied continuously within a given range, providing virtually an infinite number of possible ratios
Gear ratio
The gear ratio of a gear train is the ratio of the angular velocity of the input gear to the angular velocity of the output gear, also known as the speed ratio of the gear train. The gear ratio can be computed directly from the numbers of teeth of the various gears that engage to form the gear...

. The multitronic system uses a link-plate chain
Chain
A chain is a sequence of connected links.Chain may also refer to:Chain may refer to:* Necklace - a jewelry which is worn around the neck* Mail , a type of armor made of interlocking chain links...

 drive, an oil-cooled
Oil cooling
Oil cooling refers to a process whereby heat is displaced from a 'hotter' object, into a cooler oil and is the principle behind oil cooler devices. The oil carrying the displaced heat usually passes through a cooling unit such as a radiator or less commonly a gas decompresser...

 multi-plate clutch (initially of six parts, later of seven to enable it to cope better with the high torque
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....

 outputs of larger turbodiesel
Turbodiesel
Turbodiesel refers to any diesel engine with a turbocharger. Turbocharging is the norm rather than the exception in modern car and truck diesel engines...

 engines), and complex electronics, to overcome the traditional shortcomings of CVTs.

multitronic (spelled by Audi with a lower-case leading 'm') is a registered trademark
Trademark
A trademark, trade mark, or trade-mark is a distinctive sign or indicator used by an individual, business organization, or other legal entity to identify that the products or services to consumers with which the trademark appears originate from a unique source, and to distinguish its products or...

 of AUDI AG.

Function

The transmission is monitored and regulated by Audi
Audi
Audi AG is a German automobile manufacturer, from supermini to crossover SUVs in various body styles and price ranges that are marketed under the Audi brand , positioned as the premium brand within the Volkswagen Group....

's "Dynamic Regulating Programme" (DRP), which tracks the driver's inputs (from how the driver applies the throttle pedal), driving conditions, and engine load - to compute the optimal gear ratio
Gear ratio
The gear ratio of a gear train is the ratio of the angular velocity of the input gear to the angular velocity of the output gear, also known as the speed ratio of the gear train. The gear ratio can be computed directly from the numbers of teeth of the various gears that engage to form the gear...

 for fuel efficiency or maximum performance, as mandated by the user. The transmission can select pre-programmed underdrive to increase performance, or overdrive to improve economy. From 2004, multitronic transmissions offered manual selection of a 'sport mode' to pre-select the performance mapping. The electronic system also includes sensors to detect whether the vehicle is traveling downhill, and provides additional engine braking
Engine braking
Engine braking is where the retarding forces within an engine are used to slow a vehicle down, as opposed to using an external braking mechanism, for example friction brakes or magnetic brakes....

 in such circumstances. multitronic also offers a number of driver-selectable fixed ratios, selectable from either the gear-lever in a sequential style, or via (optional) steering wheel-mounted fingertip paddle-shift controls.

Early versions offered six ratios; in 2004, this was increased to seven, while new Audi models now have multitronic transmission with eight ratios. Some Audi A6
Audi A6
The Audi A6 is an executive car marketed by the German automaker Audi AG, now in its fourth generation. As the successor to the Audi 100, the A6 is manufactured in Neckarsulm, Germany – and is available in saloon, and wagon configurations, the latter marketed by Audi as the Avant.All generations...

 variants that feature the multitronic transmission are now equipped with the fingertip controls as standard. These controls can also switch to semi-automatic mode when one of the paddles is activated; however, they revert to fully automatic after a predetermined period of time of inactivity.

Real world performance

multitronic offers performance and economy similar to, and in some cases better than, the equivalent five-speed manual gearboxes, and superior to the traditional automatic transmission
Automatic transmission
An automatic transmission is one type of motor vehicle transmission that can automatically change gear ratios as the vehicle moves, freeing the driver from having to shift gears manually...

. Particular performance advantages are noticed with 'in-gear' seamless acceleration times over equivalent manual transmission cars.

multitronic is offered on front wheel drive-only versions of the Audi A4
Audi A4
The first generation Audi A4 debuted in 1994, with production starting November 1994. It was built on the Volkswagen Group B5 platform, which it shared with the fourth generation Volkswagen Passat . It had a front-mounted longitudinal engine and front-wheel drive...

, Audi A5
Audi A5
The Audi A5 is a coupé produced by the German automobile manufacturer Audi since 2007. It is the coupé, cabriolet, and five-door fastback versions of the fourth generation Audi A4 saloon and estate models....

, Audi A6
Audi A6
The Audi A6 is an executive car marketed by the German automaker Audi AG, now in its fourth generation. As the successor to the Audi 100, the A6 is manufactured in Neckarsulm, Germany – and is available in saloon, and wagon configurations, the latter marketed by Audi as the Avant.All generations...

, and the SEAT Exeo
SEAT Exeo
The SEAT Exeo is a five-seat large family car, and flagship model, built by the Spanish car manufacturer, and Volkswagen Group subsidiary SEAT, S.A., with factory production commencing in December 2008....

 with the 2.0 TSI gasoline engine . It is not compatible with the quattro four-wheel drive system, nor transverse engine
Transverse engine
A transverse engine is an engine mounted in a vehicle so that the engine's crankshaft axis is perpendicular to the long axis of the vehicle. Many modern front wheel drive vehicles use this engine mounting configuration...

 installations such as in the Audi A3
Audi A3
The Audi A3 is a small family car produced by the German automaker Audi since 1996. Two generations of A3 exist, both based on the Volkswagen Group A platform, which they share with several other models such as the Audi TT, Volkswagen Golf, Volkswagen Caddy and Volkswagen Touran as well as SEAT...

. At first, the torque limit was 310 newton metres (229 ft·lbf), but the transmission is now modified to withstand 400 newton metres (295 ft·lbf) torque.

Promotional campaign

In 2001, Audi promoted the multitronic transmission with television commercials throughout Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

, featuring an impersonator of musician and actor Elvis Presley
Elvis Presley
Elvis Aaron Presley was one of the most popular American singers of the 20th century. A cultural icon, he is widely known by the single name Elvis. He is often referred to as the "King of Rock and Roll" or simply "the King"....

. A prototypical dashboard figure - later named "Wackel-Elvis
Wackel-Elvis
Wackel-Elvis is a circa tall, hanging dashboard figure designed to resemble musician and actor Elvis Presley. A prototype of the figure was first introduced by the German automobile manufacturer Audi in a series of television commercials which were broadcast in several European countries...

" ("Wobble Elvis" or "Wobbly Elvis") - appeared in the commercials to demonstrate the smooth ride in an Audi equipped with the multitronic transmission. The dashboard figure was originally intended for use in the commercials only, but after they aired the demand for Wackel-Elvis grew among fans and the figure was mass produced in China and marketed by Audi in their factory outlet store.
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