GM 6L transmission explained

6L 45 · 6L 50 · 6L 80 · 6L 90
Production:	2005–present
Manufacturer:	General Motors
Class:	6-Speed Longitudinal Automatic Transmission
Predecessor:	4L60-E · 4L65-E 5L40-E · 5L50
Successor:	8L 45 · 8L 90
Related:	Aisin AWTF-80 SC Ford 6R ZF 6HP

The 6L 50 (and similar 6L 45) is a 6-speed longitudinally-mounted automatic transmission produced by General Motors. 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; Silao, Guanajuato, Mexico; and by the independent Punch Powerglide company in Strasbourg, France.

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 sedan and Cadillac SRX crossover, and replaces the 5L40-E and 5L50 in GM's lineup. The 6L 45 version is used in certain BMW vehicles and the Cadillac ATS, as part of either rear-wheel drive and all-wheel drive powertrains.

The 6L 80 (and similar 6L 90) is a six-speed automatic transmission built by General Motors at its Willow Run Transmission plant in Ypsilanti, MI. 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 Strasbourg, France.

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 plant in Toledo, Ohio to produce the 6L 80 in 2008. Torque rating 6L 80 800Nm, 6L 90 1200Nm and is adaptable to rear-wheel drive and all-wheel drive applications.

Specifications

Basic concept

A conventional planetary gearset and a compound Ravigneaux gearset is combined in a Lepelletier gear mechanism,^[1] to reduce both the size and weight. It was first realized with the 6HP from ZF Friedrichshafen. Like all transmissions realized with Lepelletier transmissions, the 6L also dispenses with the use of the direct gear ratio, making it one of the very few automatic transmission concepts without such a ratio.

It also has the capability to achieve torque converter lock-up on all six forward gears, and disengage it completely when at a standstill, significantly closing the fuel efficiency gap between automatic and manual transmissions.

Technical data

Features!!6L 45 MYA · 6L 50 MYB!6L 80 MYC · 6L 90 MYD

Colspan=3	Input Capacity
Maximum engine power	315abbr=onNaNabbr=on	555abbr=onNaNabbr=on
Maximum gearbox torque	450Nm 480Nm	800Nm 1200Nm
Maximum shift speed	7,000/min	6,200/min
Vehicle
Maximum Validated Weight Gross Vehicle Weight · GVW	5000lb 3000kg (7,000lb)	15000lb
Maximum Validated Weight Gross Curb Vehicle Weight · GCVW	12500lb	21000lb
Gearbox
7-position quadrant	P · R · N · D · X · X · X
Case material	Die cast aluminum
Shift pattern (2)	Three-way on/off solenoids
Shift quality	Five variable bleed solenoid
Torque converter clutch	Variable Bleed Solenoid ECCC
Converter size	240mm	258mm
Fluid type	DEXRON VI
Fluid capacity	9.1 kg with 258 & 300 mm
Available Control Features
Shift Patterns	Multiple (Selectable)
Driver Shift Control	Tap Up · Tap Down
Shifting	Enhanced Performance Algorithm Shifting (PAS)
Additional Modes	Tow & Haul Mode (Selectable)
Engine Torque Management	On All Shifts
Shift Control	Altitude & Temperature Compensation Adaptive Shift Time Neutral Idle Reverse Lockout Automatic Grade Braking
Additional Features
Control	OBDII · EOBD Integral Electro/Hydraulic Controls Module (Tehcm) Control Interface Protocol – GMLAN The transmission control module (TCM) is built into the solenoid pack/housing
Assembly sites	GMPT Strasbourg · France GMPT Toledo · Ohio · USA GMPT Silao · Mexico

With Assessment!colspan=3

Planetary Gearset: Teeth Lepelletier Gear Mechanism	Count	Total	Avg.
Simple				Ravigneaux
Model	Version First Delivery	S1 R1	S2 R2	S3 R3	Brakes Clutches	Ratio Span	Gear Step
Gear Ratio	R {i _{R}}	1 {i _{1}}	2 {i _{2}}	3 {i _{3}}	4 {i _{4}}	5 {i _{5}}	6 {i _{6}}
Step	- \tfrac{i _{R}} {i _{1}}	\tfrac{i _{1}} {i _{1}}	\tfrac{i _{1}} {i _{2}}	\tfrac{i _{2}} {i _{3}}	\tfrac{i _{3}} {i _{4}}	\tfrac{i _{4}} {i _{5}}	\tfrac{i _{5}} {i _{6}}
Step 2			\tfrac{i _{1}} {i _{2}} : \tfrac{i _{2}} {i _{3}}	\tfrac{i _{2}} {i _{3}} : \tfrac{i _{3}} {i _{4}}	\tfrac{i _{3}} {i _{4}} : \tfrac{i _{4}} {i _{5}}	\tfrac{i _{4}} {i _{5}} : \tfrac{i _{5}} {i _{6}}
Shaft Speed	\tfrac{i _{1}} {i _{R}}	\tfrac{i _{1}} {i _{1}}	\tfrac{i _{1}} {i _{2}}	\tfrac{i _{1}} {i _{3}}	\tfrac{i _{1}} {i _{4}}	\tfrac{i _{1}} {i _{5}}	\tfrac{i _{1}} {i _{6}}
Δ Shaft Speed	0 - \tfrac{i _{1}} {i _{R}}	\tfrac{i _{1}} {i _{1}} - 0	\tfrac{i _{1}} {i _{2}} - \tfrac{i _{1}} {i _{1}}	\tfrac{i _{1}} {i _{3}} - \tfrac{i _{1}} {i _{2}}	\tfrac{i _{1}} {i _{4}} - \tfrac{i _{1}} {i _{3}}	\tfrac{i _{1}} {i _{5}} - \tfrac{i _{1}} {i _{4}}	\tfrac{i _{1}} {i _{6}} - \tfrac{i _{1}} {i _{5}}
6L 45 MYA 6L 50 MYB	500Nm 2005	49 89	37 47	47 97	2 3
Gear Ratio		\tfrac{ 13 , 386 }{ 3 , 293 }		\tfrac{ 138 }{ 89 }		\tfrac{ 13 , 386 }{ 15 , 689 }	\tfrac{ 97 }{ 144 }
Step		1.0000		1.5293		1.3557	1.2662
Step 2				1.1408		1.0703
Speed	–1.2703	1.0000	1.7143	2.6216		4.7643	6.0346
Δ Speed	1.2703	1.0000	0.7143	0.9073		1.2499	1.2703
6L 80 MYC 6L 90 MYD	800Nm 2005	50 94	35 46	46 92	2 3
Gear Ratio		\tfrac{ 6 , 624 }{ 1 , 645 }		\tfrac{ 72 }{ 47 }		\tfrac{ 144 }{ 169 }	\tfrac{ 2 }{ 3 }
Step		1.0000		1.5429		1.3522	1.2781
Step 2				1.1604		1.0580
Speed	–1.3143	1.0000	1.7037	2.6286		4.7258	6.0401
Δ Speed	1.3143	1.0000	0.7037	0.9249		1.2310	1.3143
ZF 6HP	All · 2000	37 71	31 38	38 85	2 3
Gear Ratio		\tfrac{ 9 , 180 }{ 2 , 201 }		\tfrac{ 108 }{ 71 }		\tfrac{ 4 , 590 }{ 5 , 293 }	\tfrac{ 85 }{ 123 }
Step		1.0000		1.5382		1.3178	1.2549
Step 2			1.1589	1.1559		1.0502
Speed	–1.2258	1.0000	1.7826	2.7419		4.8096	6.0354
Δ Speed	1.2258	1.0000	0.7826	0.9593		1.1599	1.2258
Ratio R & Even	- \tfrac{R _{3} (S _{1+} R _{1)}{R} _{1} S _{3} }	\tfrac{R _{3} (S _{1+} R _{1)} (S _{2} + R _{2} )}{R _{1} S _{2} (S _{3} + R _{3} )}		\tfrac{R _{2} R _{3} (S _{1+} R _{1)}{R} _{2} R _{3} (S _{1+} R _{1)-} S _{1} S _{2} S _{3} }		\tfrac{R _{3} }
Ratio Odd	\tfrac{R _{2} R _{3} (S _{1+} R _{1)}{R} _{1} S _{2} S _{3} }		\tfrac{S _{1} + R _{1} }		\tfrac{R _{3} (S _{1+} R _{1)}{R} _{3} (S _{1+} R _{1)+} S _{1} S _{3} }
Algebra And Actuated Shift Elements
Brake A		❶	❶	❶	❶
Brake B	❶			❶		❶
Clutch C			❶				❶
Clutch D	❶	❶
Clutch E					❶	❶	❶

Applications

6L 45 MYA

• 2007–2010: BMW X3 - 3.0si / 2.5si / 3.0i
• 2007–2013: BMW 3 series - 330(x)i / 328(x)i / 325(x)i / 323i / 320i / 318i / 316i
• 2007–2019: BMW 1 series - 130i / 128i / 125i / 120i / 118i / 116i
• 2009–2015: BMW X1 (E84) - 2.8i xDrive / 2.5i xDrive / 1.8i sDrive
• 2013–2015: Cadillac ATS^[2]
• 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: Cadillac STS
• 2007–2009: Cadillac SRX
• 2008–2015: Cadillac CTS
• 2010–2015: Camaro LS/LT (V6 Models)
• 2009–2011: Holden VE Commodore / Holden VE Berlina / Holden VE Calais / Chevrolet Lumina / Chevrolet Omega
• 2009–2011: Holden WM Statesman/Caprice / Daewoo Veritas
• 2015–2022: Chevrolet Colorado^[3]
• 2017–2020: Tata Hexa
• 2019–present: UAZ Patriot
• 2022–present: Bremach^[4]

6L 80 MYC

• 2006–2009 Cadillac XLR-V^[5]
• 2006–2013 Chevrolet Corvette
• 2006 Holden VE Commodore/2008-2009 Pontiac G8
• 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
• 2007–2015 Cadillac Escalade ESV
• 2007–2013 Cadillac Escalade EXT
• 2007–2015 GMC Yukon Denali
• 2009–2020 Chevrolet Tahoe
• 2009–2020 GMC Yukon
• 2009–2020 Chevrolet Suburban 1500
• 2009–2020 GMC Yukon XL
• 2008–2009 Hummer H2
• 2014–2019 (K2XX) Chevrolet Silverado/GMC Sierra 1500
• 2010–2015 Chevrolet Camaro
• 2011–2017 Chevrolet Caprice PPV
• 2011(September)–2013 Holden VE Commodore Series 2(MY 2012)
• 2014–2017 Holden VF Commodore / Chevrolet SS
• 2009–2013 Chevrolet Avalanche
• 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 2500–3500
• 2010–present GMC Savana 2500–3500
• 2008–2019 Chevrolet Suburban 2500
• 2009–2013 Cadillac CTS-V
• 2012–2015 Chevrolet Camaro ZL1
• 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

See also

• List of GM transmissions
• Web site: GM Launches More Fuel-Saving Six-Speed Automatic Transmissions. GM Media Online. June 18, 2006.
• Cadillac PDF info on 6L 80-E Transmission: http://www.cadillacfaq.com/stsfaq/tsb/data/tsb/05-07-30-023.pdf
• Web site: GM Ypsilanti Begins 6-Speed Production . Automotive Design and Production . January 3, 2006 . dead . https://web.archive.org/web/20060303042833/http://www.automfg.com/articles/wip/1205wip04.html . March 3, 2006 .

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/

Notes and References

1. Web site: Riley . Mike . 2013-09-01 . Lepelletier Planetary System . 2023-03-03 . Transmission Digest. 2023-06-21 . https://web.archive.org/web/20230621163418/https://www.transmissiondigest.com/lepelletier-planetary-system/ . live .
2. Book: Csere, Csaba . Csaba Csere

   . Csaba Csere . Dissected: 2013 Cadillac ATS. Car and Driver . 38224673 . March 2012 . 9781858941905 . 2012-11-21 . https://web.archive.org/web/20121030060927/http://www.caranddriver.com/features/dissected-2013-cadillac-ats-feature . 2012-10-30 . live .

3. Web site: 2015 Chevrolet Colorado Specifications. GM . 2014-10-14.
4. Web site: Bremach Suv .
5. News: GM Corporate Newsroom - United States - Home. media.gm.com. 2016-10-26.