Two areas where automakers will be looking to improve corporate wide fuel economy is with the engine and with transmissions. Fuel efficient engines that still pack enough punch are important, but so is pairing that engine with a transmission that works in sync. Many automakers have been developing a variety of engine choices to improve fuel economy, but they are also building all-new transmissions.
General Motors and Ford teamed up a few years back to begin building a six-speed automatic transmission, a project neither automaker could tackle individually. By sharing costs, each automaker has been able to provide an important engineering component to keep pace with the competition.
GM’s 6T40 transmission is the latest offering from General Motors which promises to help motorists achieve superior fuel economy. Based on the earlier 6T45 — a transmission which could serve both front and all wheel drive — the 6T40 is being paired with the ECOTEC 2.4L. The result is that a car such as the mid-size Chevrolet Malibu can give class-leading fuel numbers of 22 city/32 highway.
The 6T40 and 6T45 are both derived from the 6T75 (pictured), the transmission jointly developed by Ford and General Motors. These newer versions belong exclusively to GM, but variants of the same are likely to be released by Ford too.
GM says the following about their new transmission:
http://www.autotrends.org/technology/transmissions/