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.
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]
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) |
The 9T50 and similar Ford 8F35 both share components with the GM 6T40 and Ford 6F35.[9]
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]