The 6L 50 (and similar 6L 45) is a 6-speed longitudinally-mounted

automatic transmission An automatic transmission (AT) or automatic gearbox is a multi-speed transmission (mechanics), transmission used in motor vehicles that does not require any input from the driver to change forward gears under normal driving conditions. The 1904 ...

produced by

General Motors General Motors Company (GM) is an American Multinational corporation, multinational Automotive industry, automotive manufacturing company headquartered in Detroit, Michigan, United States. The company is most known for owning and manufacturing f ...

. It is very similar in design to the larger GM 6L 80 and 6L 90, and is produced at GM Powertrain plants in

Toledo, Ohio Toledo ( ) is a city in Lucas County, Ohio, United States, and its county seat. It is located at the western end of Lake Erie along the Maumee River. Toledo is the List of cities in Ohio, fourth-most populous city in Ohio and List of United Sta ...

;

Silao, Guanajuato Silao is a municipality in the west-central part of the state of Guanajuato in Mexico. Its seat is the city of the same name. This municipality lies adjacent to the west side of the municipality of Guanajuato, the state capital. This municipalit ...

, Mexico; and by the independent Punch Powerglide company in

Strasbourg, France Strasbourg ( , ; ; ) is the prefecture and largest city of the Grand Est region of eastern France, in the historic region of Alsace. It is the prefecture of the Bas-Rhin department and the official seat of the European Parliament. The cit ...

. This transmission features clutch to clutch shifting, eliminating the bands used on older transmission designs. The 6L 50 debuted for the 2007 model year on the V8-powered versions of the

Cadillac STS The Cadillac STS (an initialism of Seville Touring Sedan) is a mid-sized luxury 4-door sedan manufactured and marketed by General Motors from 2004 to 2011 for the 2005 to 2011 model years. A version of the STS was marketed in China as the SLS ...

sedan and

Cadillac SRX The Cadillac SRX is a mid-size luxury SUV and compact luxury crossover SUV (CUV) manufactured and marketed by Cadillac over two generations: the first generation as a five-door, three-row, seven-passenger CUV (2003–2009), and the second gene ...

crossover, and replaces the 5L40-E and 5L50 in GM's lineup. The 6L 45 version is used in certain

BMW Bayerische Motoren Werke AG, trading as BMW Group (commonly abbreviated to BMW (), sometimes anglicised as Bavarian Motor Works), is a German multinational manufacturer of vehicles and motorcycles headquartered in Munich, Bavaria, Germany. Th ...

vehicles and the

Cadillac ATS The Cadillac ATS is a compact executive car (D-segment) manufactured by General Motors and marketed by Cadillac from 2012 to 2019, available in both four-door sedan and two-door coupé body styles. In the US, it is the brand's first locally-buil ...

, as part of either

rear-wheel drive Rear-wheel drive (RWD) is a form of engine and transmission layout used in motor vehicles, in which the engine drives the rear wheels only. Until the late 20th century, rear-wheel drive was the most common configuration for cars. Most rear-whee ...

and

all-wheel drive An all-wheel drive vehicle (AWD vehicle) is one with a powertrain capable of providing power to all its wheels, whether full-time or on-demand. Types The most common forms of all-wheel drive are: ;1x1 : All unicycles Reflects one axle with ...

powertrains. The 6L 80 (and similar 6L 90) is a 6-speed

built by

at its

Willow Run Transmission Willow Run Transmission (also called Ypsilanti Transmission Operations, YTO) was a General Motors factory in Ypsilanti Township, Michigan. Acquired by GM in 1953, it produced Hydramatic and other automatic transmissions for use in vehicles built by ...

plant in

Ypsilanti, MI Ypsilanti ( ), commonly shortened to Ypsi ( ), is a college town and city located on the Huron River in Washtenaw County in the U.S. state of Michigan. As of the 2020 census, the city's population was 20,648. The city is bounded to the north b ...

. It was introduced in late 2005, and is very similar in design to the smaller 6L 45 and 6L 50, produced at GM Powertrain in

. It features clutch to clutch shifting, eliminating the one-way clutches used on older transmission designs. In February 2006 GM announced that it would invest $500 million to expand the

Toledo Transmission Toledo Propulsion Systems (previously called Toledo Transmission Operations, TTO, and Powertrain Toledo) is a 2.8 million square feet; 151 acres General Motors transmission factory in Toledo, Ohio. The plant manufactures and assembles GM’s six ...

plant in

to produce the 6L 80 in 2008. 6L 80 and 6L 90 are adaptable to

and

applications.

Specifications

Technical Data

Progress Gearset Concept

Main Objectives

The main objective in replacing the predecessor model was to improve vehicle fuel economy with extra speeds and a wider gear span to allow the engine speed level to be lowered (downspeeding). The layout brings the ability to shift in a non-sequential manner – going from gear 6 to gear 2 in extreme situations simply by changing one shift element (actuating clutch E and releasing brake A).

Extent

In order to increase the number of ratios, ZF has abandoned the conventional design method of limiting themselves to pure in-line

epicyclic gearing An epicyclic gear train (also known as a planetary gearset) is a gear reduction assembly consisting of two gears mounted so that the center of one gear (the "planet") revolves around the center of the other (the "sun"). A carrier connects the ...

and extended it to a combination with parallel

. This was only possible thanks to computer-aided design and has resulted in a globally patent for this gearset concept. The 6L is based on the 6HP from ZF, which was the first transmission designed according to this new paradigm. After gaining additional gear ratios only with additional components, this time the number of components has to decrease while the number of ratios still increase. The progress is reflected in a much better ratio of the number of gears to the number of components used compared to existing layouts.

Quality Gearset Concept

The ratios of the 6 gears are nicely evenly distributed in all versions. Exceptions are the large step from 1st to 2nd gear and the almost geometric steps from 3rd to 4th to 5th gear. They cannot be eliminated without affecting all other gears. As the large step is shifted due to the large span to a lower speed range than with conventional gearboxes, it is less significant. As the gear steps are smaller overall due to the additional gear(s), the geometric gear steps are still smaller than the corresponding gear steps of conventional gearboxes. Overall, therefore, the weaknesses are not overly significant. As the selected gearset concept saves up to 2 components compared to 5-speed transmissions, the advantages clearly outweigh the disadvantages. It has a

torque converter A torque converter is a device, usually implemented as a type of fluid coupling, that transfers rotating power from a prime mover, like an internal combustion engine, to a rotating driven load. In a vehicle with an automatic transmission, the ...

lock-up for all 6 forward gears, which can be fully disengage when stationary, largely closing the

fuel efficiency Fuel efficiency (or fuel economy) is a form of thermal efficiency, meaning the ratio of effort to result of a process that converts chemical energy, chemical potential energy contained in a carrier (fuel) into kinetic energy or Mechanical work, w ...

gap between vehicles with automatic and

manual transmission A manual transmission (MT), also known as manual gearbox, standard transmission (in Canadian English, Canada, British English, the United Kingdom and American English, the United States), or stick shift (in the United States), is a multi-speed ...

s. In a Lepelletier gearset, a conventional

planetary gearset An epicyclic gear train (also known as a planetary gearset) is a gear reduction assembly consisting of two gears mounted so that the center of one gear (the "planet") revolves around the center of the other (the "sun"). A carrier connects the ...

and a composite Ravigneaux gearset are combined to reduce both the size and weight as well as the manufacturing costs. Like all transmissions realized with Lepelletier transmissions, the ''6L'' also dispenses with the use of the direct gear ratio and is thus one of the very few automatic transmission concepts without such a ratio.

Applications

6L 45 · MYA

* 2007–2010:

BMW X3 The BMW X3 is an SUV manufactured by BMW since 2003, based on the BMW 3 Series platform. BMW markets the car as a ''Sports Activity Vehicle'', the company's proprietary descriptor for its X-line luxury vehicles. The first-generation X3 was des ...

- 3.0si / 2.5si / 3.0i * 2007–2013:

BMW 3 series The BMW 3 series is a line of compact executive cars manufactured by the German automaker BMW since May 1975. It is the successor to the 02 series and has been produced in seven generations. The first generation of the 3 Series was only avail ...

- 330(x)i / 328(x)i / 325(x)i / 323i / 320i / 318i / 316i * 2007–2019:

BMW 1 series The BMW 1 Series is a range of subcompact executive cars (C-segment) manufactured by BMW since 2004. It is the successor to the BMW 3 Series Compact and is currently in its fourth generation. Positioned as the entry-level model in BMW range of ...

- 130i / 128i / 125i / 120i / 118i / 116i * 2009–2015:

BMW X1 (E84) The E84 BMW X1 is a subcompact crossover SUV/C-segment model was produced from 2009 to 2015. It is the first generation model of the BMW X1 range, and was replaced by the BMW X1 (F48), F48 BMW X1 in mid-2015. Development and launch Developmen ...

- 2.8i xDrive / 2.5i xDrive / 1.8i sDrive * 2013–2015:

* 2010–2013: Cadillac SLS * 2012–2017: Chevrolet Caprice PPV V6 * 2011–2013: Holden VE Commodore, Calais, SV6 * 2013–2017: Holden VF Commodore, Calais, SV6

6L 50 · MYB

* 2007–2011: Cadillac SLS * 2007–2011:

* 2007–2009:

* 2008–2015:

Cadillac CTS The Cadillac CTS is a luxury car, manufactured and marketed by General Motors from 2003 until 2019 across three generations. Initially available as a 4-door sedan using the GM Sigma platform, GM offered the second generation CTS in 4-door ...

* 2010–2015: Camaro LS/LT (V6 Models) * 2009–2011:

Holden VE Commodore The Holden Commodore (VE) is a full-size car that was produced from 2006 to 2013 by Holden, the former Australian subsidiary of General Motors. Dubbed Holden's "billion dollar baby", the car was available as the Holden Berlina—the mid-rang ...

/ Holden VE Berlina / Holden VE Calais /

Chevrolet Lumina The Chevrolet Lumina is a mid-size car that was produced and marketed by the Chevrolet division of General Motors from 1989 until 2001. Background The first generation of the Lumina replaced the Chevrolet Celebrity and Chevrolet Monte Carlo ...

/ Chevrolet Omega * 2009–2011: Holden WM Statesman/Caprice / Daewoo Veritas * 2015–2022:

Chevrolet Colorado The Chevrolet Colorado (sharing mechanical commonality with the GMC Canyon) is a series of compact pickup trucks (mid-size since second generation) marketed by American automaker General Motors. They were introduced in 2004 to replace the Chevrol ...

* 2017–2020:

Tata Hexa Tata Hexa was a mid-size crossover SUV manufactured by Indian passenger and commercial vehicles manufacturer Tata Motors. A heavily reworked Tata Aria, the Hexa was originally unveiled in the 2016 Geneva Motor Show and was launched into the Indi ...

* 2019–present:

UAZ Patriot The UAZ Patriot ( AZ-3163 is a mid-size body-on-frame SUV produced by the UAZ division of Sollers in Ulyanovsk, Russia. It was introduced in 2005 and replaced the older UAZ Simbir (UAZ-3162). Extensive use of newer parts, large carrying c ...

* 2022–present:

Bremach Bremach was an Italy, Italian/United States, American manufacturer of tactical trucks specializing in the manufacturing of military vehicles and 4WD fire engines. History Bremach was founded in 1956 in the city of Varese (northern Italy) by t ...

6L 80 · MYC

* 2006–2009 Cadillac XLR-V * 2006–2013

Chevrolet Corvette The Chevrolet Corvette is a line of American two-door, two-seater sports cars manufactured and marketed by General Motors under the Chevrolet marque since 1953. Throughout eight generations, indicated sequentially as C1 to C8, the Corvette is not ...

* 2006

/2008-2009

Pontiac G8 The Pontiac G8 is a full-size sedan that was produced by Holden in Australia for export to the United States, where it was sold by Pontiac. The G8, a rebadged Holden Commodore, was released in early 2008 for the 2008 model year in the United Stat ...

* 2006–2013 Holden/Chevrolet WM Statesman/Caprice * 2014–2017 Holden/Chevrolet WN Statesman/Caprice * 2007–2013 GMC Sierra Denali * 2009–2013 Chevrolet Silverado 1500 5.3 (ext. & crew cab), 6.2 * 2009–2013 GMC Sierra 1500 5.3 (ext. & crew cab), 6.2 * 2010–2013 Chevrolet Silverado 1500 5.3 (reg. cab) * 2010–2013 GMC Sierra 1500 5.3 (reg. cab) * 2006–2009 Cadillac STS-V * 2007–2015

Cadillac Escalade The Cadillac Escalade is a full-size luxury SUV manufactured by General Motors and marketed by their luxury division Cadillac. It was the luxury brand's first major entry into the SUV market. The Escalade was introduced for the 1999 model year ...

* 2007–2015

Cadillac Escalade ESV The Cadillac Escalade is a full-size luxury SUV manufactured by General Motors and marketed by their luxury division Cadillac. It was the luxury brand's first major entry into the SUV market. The Escalade was introduced for the 1999 model year ...

* 2007–2013

Cadillac Escalade EXT The Cadillac Escalade is a full-size luxury SUV manufactured by General Motors and marketed by their luxury division Cadillac. It was the luxury brand's first major entry into the SUV market. The Escalade was introduced for the 1999 model year ...

* 2007–2015

GMC Yukon Denali The Chevrolet Tahoe (), and its badge-engineered GMC Yukon counterpart, are full-size SUVs and other trucks from General Motors, offered since 1994 and 1991, respectively. Since 1982, Chevrolet and GMC sold two different-sized SUVs under thei ...

* 2009–2020

Chevrolet Tahoe The Chevrolet Tahoe (), and its Rebadging, badge-engineered GMC Yukon counterpart, are full-size SUVs and other trucks from General Motors, offered since 1994 and 1991, respectively. Since 1982, Chevrolet and GMC (General Motors division), GMC ...

* 2009–2020

GMC Yukon GMC may refer to: Government India * Gandhinagar Municipal Corporation, in Gujarat * Gobichettipalayam Municipal Corporation, in Tamil Nadu * Guntur Municipal Corporation, in Andhra Pradesh * Guwahati Municipal Corporation, in Assam * Gwalior ...

* 2009–2020

Chevrolet Suburban The Chevrolet Suburban is a series of SUVs built by Chevrolet since the 1935 model year. The longest-used automobile nameplate in the world, the Chevrolet Suburban is currently in its twelfth generation, introduced for 2021. Beginning life a ...

1500 * 2009–2020

GMC Yukon XL GMC may refer to: Government India * Gandhinagar Municipal Corporation, in Gujarat * Gobichettipalayam Municipal Corporation, in Tamil Nadu * Guntur Municipal Corporation, in Andhra Pradesh * Guwahati Municipal Corporation, in Assam * Gwalior Mu ...

* 2008–2009

Hummer H2 The Hummer H2 is a full-size off-road sport utility vehicle (SUV) that was marketed by Hummer and built in the AM General facility under contract from General Motors from 2002 until 2009. It is based on a modified GMT820 GM three-quarter-ton pi ...

* 2014–2019 (K2XX) Chevrolet Silverado/GMC Sierra 1500 * 2010–2015

Chevrolet Camaro The Chevrolet Camaro is a mid-size American automobile manufactured by Chevrolet, classified as a pony car. It first went on sale on September 29, 1966, for the 1967 model year and was designed to compete with the Ford Mustang. The Camaro sha ...

* 2011–2017

Chevrolet Caprice PPV The Chevrolet Caprice is a full-size car produced by Chevrolet in North America for the 1965 through 1996 model years. Full-size Chevrolet sales peaked in 1965, with over a million units sold. It was the most popular car in the U.S. in the 19 ...

* 2011(September)–2013 Holden VE Commodore Series 2(MY 2012) * 2014–2017

Holden VF Commodore The Holden Commodore (VF) is a full-size car that was produced by Holden between June 2013 and October 2017. It was the second and last significantly restyled iteration of the fourth (and final) generation of the Holden Commodore to be manufac ...

Chevrolet SS The Holden Commodore (VF) is a full-size car that was produced by Holden between June 2013 and October 2017. It was the second and last significantly restyled iteration of the fourth (and final) generation of the Holden Commodore to be manufac ...

* 2009–2013

Chevrolet Avalanche The Chevrolet Avalanche is a four-door, five- or six-passenger pickup truck that was manufactured by General Motors. The Avalanche was a hybrid between the Chevrolet Suburban SUV and the Chevrolet Silverado pickup truck, sharing the chassis with t ...

* 2019–2021 (T1XX) Chevrolet Silverado/GMC Sierra 1500

6L 90 · MYD

* 2007–2014 Chevrolet Silverado 2500HD/3500 HD 6.0 * 2007–2014 GMC Sierra 2500HD/3500HD 6.0 * 2010–present

Chevrolet Express The Chevrolet Express (also known as the GMC Savana) is a series of full-size vans produced by General Motors since 1996. The successor to the Chevrolet G-series van, the Express is produced in passenger and cargo variants. Alongside the stan ...

2500–3500 * 2010–present

GMC Savana Savana is a town and commune in Madagascar. It belongs to the district of Vohipeno, which is a part of Vatovavy-Fitovinany Region. The population of the commune was estimated to be approximately 4,000 in the 2001 commune census. Only primary s ...

2500–3500 * 2008–2019

2500 * 2009–2013

Cadillac CTS-V The Cadillac CTS is a luxury car, manufactured and marketed by General Motors from 2003 until 2019 across three generations. Initially available as a 4-door sedan using the GM Sigma platform, GM offered the second generation CTS in 4-door s ...

* 2012–2015

Chevrolet Camaro ZL1 The Chevrolet Camaro is a mid-size American automobile manufactured by Chevrolet, classified as a pony car. It first went on sale on September 29, 1966, for the 1967 model year and was designed to compete with the Ford Mustang. The Camaro shar ...

* 2015–2019 Chevrolet Silverado 2500HD/3500 HD 6.0 * 2015–2019 GMC Sierra 2500HD/3500HD 6.0 * 2020–2023 Chevrolet Silverado 2500HD/3500 HD 6.6 L8T * 2020–2023 GMC Sierra 2500HD/3500HD 6.6 L8T

References

External links

General Motors Powertrain Division
* https://gmauthority.com/blog/gm/gm-transmissions/mya/ * https://gmauthority.com/blog/gm/gm-transmissions/myb/ * https://gmauthority.com/blog/gm/gm-transmissions/myc/ * https://gmauthority.com/blog/gm/gm-transmissions/myd/ {{Powertrain 6L

Specifications

Technical Data

Progress Gearset Concept

Main Objectives

Extent

Quality Gearset Concept

Applications

6L 45 · MYA

6L 50 · MYB

6L 80 · MYC

6L 90 · MYD

See also

References

External links