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Various products with paper-based wet-friction material have been developed for smoother shifting of automatic transmissions. Band brakes have been featured as friction engagement elements for planetary gears, which provide higher holding-torque capacity than same-size multiple friction-disk brakes caused by a self-energizing mechanism. The advantages that should be focused on are better shift quality for the release element during up shifting because of the different torque capacity in the drum rotating direction. In 1988, BorgWarner developed the Maji-Band for band brakes (coiled-steel straps joined into bands), which is lightweight and compact, and provides approximately 3.5 times higher torque capacity than single wrapped band brakes and lower drag torque than multiple friction-disk brakes. However, it is difficult to control shift quality as the engaging element for upshifting is caused by instability in attaining the required torque to dynamically follow the servo-applied force.

Reducing loss torque in automatic transmissions (ATs) is a key factor in improving fuel economy. A promising approach is to reduce the viscosity of the Automatic Transmission Fluid (ATF) so as to minimize churning loss. Aisin AW and JXTG Nippon Oil & Energy Corporation have developed a super low viscosity ATF, called “AW-2”, which has approximately 50% lower kinematic viscosity at 40 °C compared to the conventional ATF “AW-1”. It is generally understood that if the viscosity of an ATF is too low, it can have a negative impact on the fatigue life of components such as gears and bearings, and possibly lead to increased wear or seizure. AW-2 was designed to solve these problems via the application of two key technologies. The first is a high performance base oil with a low traction coefficient, which translates to low viscosity under high pressure conditions.