In April of 2013, Ford and General Motors announced they would be working together on developing new nine and ten-speed automatic transmissions. The nine-speed automatic would be for front-wheel drive models, while rear-drive models got the ten-speed. Already, a number of Ford and GM vehicles are using the ten-speed. But GM will be the only one using the nine-speed.
Automotive News reports that Ford is electing to use a new series of eight-speed automatic transmission on their vehicles. The company said the new nine-speed didn't provide enough of an improvement in fuel economy to justify the added cost and weight. According to a source, Ford made this decision before GM began to use this transmission on their production models.
"Typically, if anyone gave me a transmission that didn't require much work, outside of tuning it for a specific vehicle, I would take it and run. It's a lot of design work after the fact to come up with their own flavor. It shows there might be some different schools of thought in terms of transmission efficiency," said Dave Sullivan, an analyst with AutoPacific Inc.
While GM claims the nine-speed brings “smoother shifts” and a better driving experience, it hasn't brought any real gains to fuel economy. The 2017 Chevrolet Malibu 2.0T only saw an increase of one mpg on the highway when compared to the 2016 model with a six-speed automatic (33 vs. 32). The 2019 Buick Envision 2.0T saw its highway fuel economy drop by one when equipped with the nine-speed auto (25 vs. 26).
It should be noted that one of the eight-speed transmissions Ford is using is based on the new nine-speed, minus a gear.
Source: Automotive News (Subscription Required)