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.
| 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 |
Design / history edit
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 edit
| 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 edit
- Applications
- 2018– GMC Terrain (1.5 L LYX & LSD)[10]
9T50 edit
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 edit
- Applications
- 2020– GMC Acadia (2.0 T LSY)[10]
9T65 edit
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 edit
References edit
- ^ Brooke, Lindsay (April 15, 2013). "Ford and GM finally consummate 9- and 10-speed joint development". Automotive Engineering. Archived from the original on March 25, 2018. Retrieved 12 December 2023.
- ^ Martinez, Michael (April 23, 2018). "No thanks, Ford says to 9-speed offered by GM". Automotive News. Retrieved 12 December 2023.
- ^ Tracy, David (April 23, 2018). "Why Ford Isn't Using GM's Nine-Speed Automatic Transmission". Jalopnik. Retrieved 12 December 2023.
- ^ Amend, James M. (December 7, 2016). "New 9-Speed Pushes Tech Limit, GM Says". Wards Auto. Retrieved 12 December 2023.
- ^ a b Riley, Mike (August 1, 2019). "General Motors 9T50 Nine Speed FWD: Part One". Transmission Digest. Retrieved 18 December 2023.
- ^ Markus, Frank (October 7, 2016). "Peeking Inside the GM/Ford Transverse Nine-Speed Automatic". Motor Trend. Retrieved 18 December 2023.
- ^ Riley, Mike (September 1, 2019). "General Motors 9T50 Nine Speed FWD: Part Two". Transmission Digest. Retrieved 18 December 2023.
- ^ "General Motors 9T50 Nove Velocidades Treinamento Técnico" [General Motors 9T50 nine-speed technical training] (PDF) (in Portuguese). Cambio Automatico do Brasil. Retrieved 12 December 2023.
- ^ a b c d Brayton, Bill (June 28, 2019). "Fun with transmissions: There's a New 9 Speed On The Block". Gears. Retrieved 12 December 2023.
- ^ a b c d "2021 GMC Trailering Guide" (PDF). General Motors. Retrieved 12 December 2023.
- ^ a b "All-New 2019 Blazer Arrives with Attitude" (PDF). TechLink. Vol. 21, no. 2. General Motors. January 2019. Retrieved 12 December 2023.
- ^ McEachern, Sam (December 3, 2020). "GM Initiates Pilot Program To Replace 9T65 9-Speed Transmission". GM Authority. Retrieved 12 December 2023.
- ^ "New 9T65 Transmission Replacement Pilot Program Bulletin Information" (PDF). TechLink. Vol. 23, no. 11. General Motors. June 2021. Retrieved 12 December 2023.
- ^ Panait, Mircea (24 March 2023). "GM Built Certain 9-Speed Transmissions Incorrectly, Recalls 7,840 SUVs". Auto Evolution. Retrieved 12 December 2023.
External links edit
- "New 9T50 9-Speed Automatic Transmission" (PDF). TechLink. Vol. 19, no. 6. General Motors. March 2017.