Chevrolet's 2017 Malibu will arrive with an optional nine-speed automatic transmission that improves fuel economy by 3% and marks the brand's first implementation of a nine-speed automatic.
The front-wheel-drive vehicle pairs the nine-speed Hydra-Matic 9T50 with the available 2.0L turbocharged inline four and replaces an eight-speed automatic transmission. Chevrolet will continue to offer the base Malibu that pairs the Hydra-Matic 6T45 six-speed automatic with the direct-injected turbo Ecotec 1.5L inline-four with variable valve timing.
The nine-speed transmission improves EPA-estimated highway fuel economy to 33 mpg for the Malibu, according to General Motors.
Chevrolet will also add the new nine-speed transmission to the 2017 Cruze Diesel and 2018 Equinox. General Motors plans to roll out the transmission as optional equipment on 10 models by the end of 2017.
The transmission uses an on-axis design, where all the gears are in line with the crankshaft and GM's first application of a selectable one-way clutch. Both features help reduce the package size, making it roughly the same size as a six-speed transmission. It was developed for a transverse engine.
The transmission uses a specific strategy in the selection of the gearsets, clutches and torque converter. Five planetary gearsets are used with four stationary clutches and three rotating clutches to save space compared to freewheeling designs. Gears change from second- to ninth-gear ratios with precise clutch-to-clutch shifting, where the clutch is engaged in one gear at exactly the same time it is released from another.
The first-to-second upshift is a freewheeling shift. The second-gear clutch engages while the first-gear one-way clutch spins freely that contributes to greater refinement at lower vehicle speeds, according to GM.
This planetary-type automatic transmission employs new torque converter technology to help it deliver smooth take-off performance and additional refinement. The converter features a hyper-elliptical oval cross-section that reduces the thickness of the torque converter, keeping the overall width of the engine and transmission as narrow as possible for packaging advantages.
The single-plate lock-up clutch uses GM’s electronically controlled capacity clutch technology to dampen engine vibrations and ensure smooth operation.