Toyota’s quiet transmission changes

Toyota announced two new transmissions today, quietly, as part of an otherwise fairly dull release on the Toyota Corolla Hatchback née Scion iM.

Toyota stick shift

First is the new K120 CVT — a continuously variable transmission, but not purely driven by belts or bands. Now, Toyota has included a special launch gear — the world’s first launch gear in a passenger-car CVT — avoiding the bands entirely. The reason is because CVTs tend to have low efficiency in lower gear ratios; so now when drivers start, they will have “gear drive,” avoiding a moment of sluggishness and wasted power. It moves from gear to belt drive after launch.

Using the belt for launches means that the belts can be tuned for higher gear ratios. Combined, the two systems bring an excellent, class-leading range of 7.5 — similar to much more expensive nine speed automatics. Reducing the torque load of the belt meant that the belt and pulley could be smaller, increasing shift speeds.

The second major announcement was a new “smart” six-speed “iMT” manual transmission, which automatically matches engine revs on downshifts for greater smoothness and, likely more important for Toyota, lower emissions. The new gearbox is also 15 pounds lighter (at 88 pounds) and shorter (by 0.94 inches).

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