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General Motors is in the late stages of developing an in-house continuously variable transmission for use around the world to meet tightening fuel-economy and carbon- dioxide emissions regulations.


Details on the CVT are limited, but sources tell WardsAuto it will find its way into several “high-volume” products by 2019, including models in the U.S., and it will mate to GM’s new family of small-displacement 3-cyl. and 4-cyl. engines rolling out this year.


Growth forecast for continuously variable transmissions, such as Nissan’s Xtronic CVT.


The CVT has reached a point in its development where GM has hosted suppliers at its global powertrain headquarters in Pontiac to solicit bids for parts.


“We can’t confirm if we are doing one,” GM Powertrain spokesman Tom Read tells WardsAuto. “Obviously, we have the capability.”


As fuel-economy and tailpipe-emissions standards tighten in markets around the world, including upwards of 54.5 mpg (4.3 L/100 km) in the U.S. by 2025, automakers are pulling all levers to remain compliant.


Gearless CVT technology would be one of the more significant moves, especially in the U.S., where consumers historically have shied away from the option because of its shiftless, unfamiliar feel.


To address U.S. customer preferences, Nissan has gone so far as to fabricate shift points into its Xtronic CVT so it mimics a traditional automatic. The CVT pushes the Altima’s highway fuel economy to an EPA-estimated 38 mpg (6.2 L/100 km).


The CVT in the Honda Accord Hybrid enables an EPA-estimated 50 mpg (4.7 L/100 km) city rating. Hybrids remain the predominant application for CVTs.


GM uses CVT technology today, too, but the applications are limited. In the U.S., the ’15 Chevy Spark offers a CVT, which the automaker sources from Japan-based Jatco. The take-rate for the Spark CVT is an impressive 70%. GM also uses a CVT as the sole transmission option for its Chevrolet City Express van, a vehicle it sources from Nissan.


GM’s previous CVTs met with mixed results. The automaker viewed it as the ideal fuel-saver in the early 2000s, outfitting it on the now-defunct Saturn Vue CUV and Ion small car, as well as the Opel Vectra in Europe. But GM encountered drivability issues and production snags and dropped the program in 2004.


The automaker said at the time it would pursue conventional automatic transmission technology because those gearboxes had become more advanced.


Ford also dumped a CVT program about the same time.


Over the years, a key hurdle for CVTs in the U.S. has been size and torque-capacity limitations, which made them appropriate only for smaller engines in a market where bigger has traditionally been better.


CVTs have remained popular with Asian automakers and Asian consumers, while Europeans have grown to favor dual-clutch transmissions to gain efficiency.


GM’s Read says the automaker will be ready with the technology if it is warranted.


“GM has unmatched transmission expertise and development resources and is capable of delivering additional CVTs if and when they’re needed,” Read adds. 


In the ’14 model year, CVTs comprised 12.1% of U.S. transmission installations, according to WardsAuto data. Traditional step-geared automatics, meanwhile, accounted for 82.9% of installations.


Globally, CVTs commanded a 10.7% share in the 2014 calendar year. According to AutoForecast solutions, the global share of CVTs will rise to 14.1% in 2020. Asia/Pacific will see most of the growth, rising to 10.6 million installations in 2020 from 6.6 million last year. In North America, penetration will grow to 3.8 million from 2.4 million.

Source: wardsauto
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