GM’s all-new Hydra-Matic 9T50 9-speed automatic transmission (RPOs M3E, M3D, M3H) — currently available on the 2017 Malibu, 2017 Cruze Diesel, 2018 Equinox and upcoming 2018 Terrain — is designed to deliver excellent efficiency, performance and refinement. (Fig. 1) By the end of this year, it will be an option on 10 GM models.
图。1
例如，当与Malibu的2.0L Turbo发动机配对时，传输有助于轿车在高速公路上提供估计的33 MPG（7.1L / 100km） - 通过8速自动变速器，2016年Malibu增加3％。
The transmission consists primarily of a 4-element torque converter, a compound planetary gear set, friction and mechanical clutch assemblies, and a hydraulic pressurization and control system. It employs a wider 7.6:1 overall ratio (compared to the 8-speed transmission) for better acceleration in first gear — 4.69 first gear — and lower engine speeds on the highway — 0.62 top gear —to enhance fuel economy and reduce noise.
设计
开发以满足严格的包装需求of transverse propulsion systems, the 9T50 features an on-axis layout that keeps the planetary gears in line with the engine crankshaft. It also has GM’s first application of a selectable one-way clutch that can hold torque or freewheel, depending on the desired operating mode.
轴轴设计和单向离合器的组合消除了对附加离合器包的需要，有助于减少整个封装尺寸，使紧凑的9T50传输大致与六速传输相同的尺寸。
变速器使用五个行星齿轮，四个固定离合器和三个旋转离合器。（图2）齿轮从2nd-to到9的比率改变，具有精确的离合器 - 离合器换档，离合器在一个齿轮中与另一个齿轮接合到另一个齿轮上从另一个齿轮释放。
图2
液压系统主要由链条驱动泵，控制阀体组件和壳体组成。泵保持冲击施加或释放摩擦部件的离合器活塞所需的工作压力。
变速器的单板锁定离合器使用电子控制的容量离合器（ECCC）来抑制发动机振动并确保平滑运行。
Shift Controls
命令所有转换事件是32位传输控制模块（TCM），位于传输之外。TCM使用自适应学习来补偿新的传输变化和应用组件的正常磨损。通过将压力指令调整到各种压力控制（PC）螺线管，它保持最初校准的换档时序，以获得一致的换档感觉加上的传动耐用性。
小费：Anytime internal repairs are performed or a revised calibration is installed, the Service Fast Learn Procedure should be performed using GDS2. This helps the transmission learn the clutch fill times initially prior to driving the vehicle. The vehicle should always be driven after the Service Fast Learn Procedure to ensure that the shift quality is acceptable.
To help maintain desired vehicle speed when coasting or braking on a hill, the transmission uses automatic grade braking that can select a lower gear to take advantage of engine braking. The control module receives inputs that monitor brake pedal usage, vehicle acceleration, throttle position, grade and whether a trailer is being towed.
9T50传输还支持自动发动机停止/启动操作。传输内的独特累加器允许精细停止/开始转换。蓄电池将能量存储用于发动机重启，而软件被校准，用于平滑重启。
9T50变速器使用Dexron®-vi液体。它不需要在正常驾驶条件下变化。
- 感谢Mark Kevnick
