Engineering:GM 9T50 transmission
| 9TXX (9T45, 9T50, 9T60, 9T65) | |
|---|---|
| Overview | |
| Manufacturer | General Motors |
| Production | 2019–present |
| Body and chassis | |
| Class | 9-speed transverse automatic transmission |
| Related | Ford 8F |
| Chronology | |
| Predecessor | 6F35/6F50/6F55 |
The General Motors Hydra-Matic 9T50 and similar 9T45, 9T60, and 9T65 are part of the 9TXX family of electronic automatic transmissions with nine forward speeds for light-duty transversely-mounted applications. It was designed and manufactured by General Motors, equipped on automobiles starting with the 2017 model year; the 9TXX family was developed from an earlier joint GM–Ford 6-speed automatic transmission. Ford sells derivatives of the 9TXX with one forward speed removed as the 8F family.
Design / history
Ford and GM announced a joint venture to share automatic transmission designs in April 2013: GM would adopt a 10-speed longitudinal transmission primarily designed by Ford, and in exchange, Ford would adopt the GM 9TXX 9-speed transverse transmission.[1] Ford declined to use the GM 9TXX, however, as the promised improvement in fuel consumption was less than expected, and removed one gear, resulting in the Ford 8F family.[2][3]
During the development of the 9TXX, GM received 60 new patents while building 800 prototypes.[4] It was developed from the 6T41 (Gen 3)[5] and designed to occupy approximately the same volume as that prior six-speed automatic and retain that transmission's on-axis design, which aligns all the planetary gears with the crankshaft. The addition of three gears was facilitated by adding a "selectable one-way clutch" which can act either as a sprag clutch, freewheeling in one direction and locking up in the other, or freewheeling in both directions. In addition, the transmission supports start-stop systems by including a spring-loaded hydraulic accumulator to engage the first-gear clutches upon restarting the engine.[6] The 8th gear ratio of the 9TXX corresponds to the 6th gear ratio of the 6T40, allowing lower engine speeds in 9th gear.[5] Two of the three planetary gear sets have similar designs between the 9TXX and 6T40; for the third, the 9TXX switches to a compound set.[7]
Models
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | R | Final drive |
|---|---|---|---|---|---|---|---|---|---|---|
| 4.69 | 3.31 | 3.01 | 2.45 | 1.92 | 1.45 | 1.00 | 0.75 | 0.62 | 2.96 | 2.89, 3.17, 3.32, 3.47, 3.63, 3.80 |
The last two digits of the model number indicate maximum GVWR and towing capacity, with higher numbers having a larger capacity.[9]
| Model | Max. trailer weight | Max. GVWR |
|---|---|---|
| 9T45 | 1,743 kg (3,843 lb) | 2,700 kg (6,000 lb) |
| 9T50 | 2,598 kg (5,728 lb) | 2,730 kg (6,020 lb) |
| 9T60 | 3,080 kg (6,790 lb) | |
| 9T65 | 2,473 kg (5,452 lb) | 2,930 kg (6,460 lb) |
9T45
- Applications
- 2018– GMC Terrain (1.5 L LYX & LSD)[10]
9T50
The 9T50 and similar Ford 8F35 both share components with the GM 6T40 and Ford 6F35.[9]
- Applications
- 2020– Cadillac XT6 (2.0 T LSY, 3.6 L LGX)
- 2019– Chevrolet Blazer (2.5 L LCV)[11]
- 2017– Chevrolet Malibu (2.0 T LTG)
- 2020– GMC Acadia (2.5 L LCV)[10]
9T60
- Applications
- 2020– GMC Acadia (2.0 T LSY)[10]
9T65
In December 2020, GM initiated a program to repair or replace 9T65 transmissions which were causing issues. Repairs were limited to external components only.[12] The program applied to vehicles that had less than 18,000 mi (29,000 km) and had been delivered within the past 18 months.[13] A recall was issued in March 2023 for certain crossover vehicles which may have a transmission that was assembled using an incorrectly sized sun gear.[14]
- Applications
- 2018– Buick Enclave (3.6 L LFY)
- 2017– Buick LaCrosse (3.6 L LGX)
- 2019– Chevrolet Blazer (3.6 L LGX)[11]
- 2018– Chevrolet Traverse (3.6 L LFY)
- 2018– GMC Acadia (3.6 L LGX)[10]
See also
References
- ↑ Brooke, Lindsay (April 15, 2013). "Ford and GM finally consummate 9- and 10-speed joint development". Automotive Engineering. http://articles.sae.org/12015/.
- ↑ Martinez, Michael (April 23, 2018). "No thanks, Ford says to 9-speed offered by GM". Automotive News. https://www.autonews.com/article/20180423/OEM01/180429934/no-thanks-ford-says-to-9-speed-offered-by-gm.
- ↑ Tracy, David (April 23, 2018). "Why Ford Isn't Using GM's Nine-Speed Automatic Transmission". Jalopnik. https://jalopnik.com/why-ford-isn-t-using-gm-s-nine-speed-automatic-transmis-1825465785.
- ↑ Amend, James M. (December 7, 2016). "New 9-Speed Pushes Tech Limit, GM Says". Wards Auto. https://www.wardsauto.com/technology/new-9-speed-pushes-tech-limit-gm-says.
- ↑ 5.0 5.1 Riley, Mike (August 1, 2019). "General Motors 9T50 Nine Speed FWD: Part One". Transmission Digest. https://www.transmissiondigest.com/general-motors-9t50-nine-speed-fwd-part-one/. Retrieved 18 December 2023.
- ↑ Markus, Frank (October 7, 2016). "Peeking Inside the GM/Ford Transverse Nine-Speed Automatic". Motor Trend. https://www.motortrend.com/news/peeking-inside-the-gmford-transverse-nine-speed-automatic/.
- ↑ Riley, Mike (September 1, 2019). "General Motors 9T50 Nine Speed FWD: Part Two". Transmission Digest. https://www.transmissiondigest.com/general-motors-9t50-nine-speed-fwd-part-two/. Retrieved 18 December 2023.
- ↑ "General Motors 9T50 Nove Velocidades Treinamento Técnico" (in pt). Cambio Automatico do Brasil. https://cambioautomaticodobrasil.com.br/painel/public/pdf/15949204245f108de8e4079.pdf.
- ↑ 9.0 9.1 9.2 9.3 Brayton, Bill (June 28, 2019). "Fun with transmissions: There's a New 9 Speed On The Block". Gears. https://gearsmagazine.com/magazine/the-8f35-a-closer-look/. Retrieved 12 December 2023.
- ↑ 10.0 10.1 10.2 10.3 "2021 GMC Trailering Guide". General Motors. https://www.gmc.com/content/dam/gmc/na/us/english/index/about/trailering-towing/02-pdfs/03-pdfs/GMTB21CT100_2021_GMC_Trailering%20Guide_DIGITAL.pdf.
- ↑ 11.0 11.1 "All-New 2019 Blazer Arrives with Attitude". TechLink (General Motors) 21 (2). January 2019. https://techlink.mynetworkcontent.com/wp-content/uploads/2019/02/GM_TechLink_02_Mid-January_2019.pdf. Retrieved 12 December 2023.
- ↑ McEachern, Sam (December 3, 2020). "GM Initiates Pilot Program To Replace 9T65 9-Speed Transmission". GM Authority. https://gmauthority.com/blog/2020/12/gm-initiates-pilot-program-to-replace-9t65-9-speed-transmission/.
- ↑ "New 9T65 Transmission Replacement Pilot Program Bulletin Information". TechLink (General Motors) 23 (11). June 2021. https://gm-techlink.com/wp-content/uploads/2021/06/GM_TechLink_11_June_2021.pdf. Retrieved 12 December 2023.
- ↑ Panait, Mircea (24 March 2023). "GM Built Certain 9-Speed Transmissions Incorrectly, Recalls 7,840 SUVs". Auto Evolution. https://www.autoevolution.com/news/gm-built-certain-9-speed-transmissions-incorrectly-recalls-7840-suvs-212336.html.
External links
- "New 9T50 9-Speed Automatic Transmission". TechLink (General Motors) 19 (6). March 2017. https://techlink.mynetworkcontent.com/wp-content/uploads/2017/05/GM_TechLink_06_Mid-March_2017.pdf.
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