Dec. 06, 2016

New 8-speed and 10-speed Automatic Transmissions (Direct Shift-8AT & Direct Shift-10AT)

 

Dec. 06, 2016

New 8-speed and 10-speed Automatic Transmissions (Direct Shift-8AT & Direct Shift-10AT)

Toyota has developed two new automatic transmissions―the 8-speed Direct Shift-8AT and the 10-speed Direct shift-10AT. For both, various measures were taken to minimize energy loss and heighten transmission efficiency. Gear tooth surfaces were processed using a new technique for a lower coefficient of friction when the gears engage, and the configuration of the friction material used inside the clutch was optimized to reduce clutch torque loss by approximately 50 percent during rotation (compared to a conventional 6-speed transmission). These and other efforts resulted in achieving one of the world's best transmission efficiencies*. The new automatic transmissions are more compact and lighter than comparative conventional transmissions, lowering a vehicle's fuel requirements. And their lower center of gravity results in both improved straight-driving stability and better cornering stability.

Furthermore, widened gears and a newly developed high-performance compact torque convertor combine for a broader gear lockup range. The resulting quick and smooth response to accelerator pedal operation creates an "as desired" direct driving feel.

In the case of the Direct Shift-10AT, even though the number of gears has been increased to 10 (compared to eight gears in the case of the Direct Shift-8AT), the use of close-ratio gears optimizes the range of use of each gear, particularly in the low-to-mid speed range. The resulting smooth gear changes, which are among the world's quickest*, create a rhythmical and comfortable sensation that is suitable for a premium rear-wheel-drive vehicle.

As of November 2016, according to Toyota survey

New FF 8-speed Automatic Transmission

  • Top-level transmission efficiency contributes to higher fuel economy, compactness, lightweight, low center of gravity contributes to driving performance
  • Lock-up range of the new 8-speed gear train is widened to realize direct response driving
New FF 8-speed Automatic Transmission

New FR 10-speed Automatic Transmission

  • In addition to its high basic performance which is common with the Direct Shift-8AT, an exhilarating driving performance for FR premium car is pursued
  • Adopting a close-ratio transmission, and its world-class top gear change speed helps to ensure smooth driving
  • Directly responding to the driver's accelerator operation
New FR 10-speed Automatic Transmission

Performance of Direct Shift-8AT

Achieved world-class top level transmission efficiency

Achieved world-class top level transmission efficiency

Realization of a more responsive driving feeling which quickly reacts to driver's acceleration operation

Realization of a more responsive driving feeling which quickly reacts to driver's acceleration operation

Compact package design achieved with Multi-shift step and high peformance

Compact package design achieved with Multi-shift step and high peformance

Details of the new technologies of Direct Shift-8AT

Low-loss torque friction plate

Lost torque was reduced by 50% with the optimization of friction plate segment shape in order to improve fluid drag force with a disengaged clutch.

Low-loss torque friction plate

High performance compact torque converter

Newly developed lock-up system enabled widening the area which car can drive while the clutch is locked-up.

High performance compact torque converter

Performance of Direct Shift-10AT

Close-ratio transmission creates a smooth and rhythmical gear change

Close-ratio transmission creates a smooth and rhythmical gear change

Fastest and shock-free gear change

Fastest and shock-free gear change

Realization of a more responsive driving feeling which reacts quickly to the driver's operation of the acceleration

Realization of a more responsive driving feeling which reacts quickly to the driver's operation of the acceleration

Details of the new technologies of Direct Shift-10AT

New 10-speed gear train

10-speed AT with minimum components
The same size with the current 8AT

New 10-speed gear train

High performance compact torque converter

Sophisticated technologies into compact size

High performance compact torque converter