sixspeed

Sixspeed, often written six-speed, is a term used in automotive engineering to denote transmissions that offer six forward gear ratios. It can refer to manual transmissions operated by a clutch, as well as automatic transmissions that select six gears through planetary gearsets or sequential actuators. In some cases, manufacturers or aftermarket suppliers use the term as a brand name or product line.

Typical layout is three pairs of gears (1-2-3-4-5-6) with a reverse gear, though some designs place the gears in different arrangements. The 6th gear is typically an overdrive for efficiency at highway speeds.

Benefits of a six-speed transmission include a wider ratio spread for better fuel economy and flexible use of engine torque; improved acceleration and performance in some configurations; and smoother cruising at cruise speeds. Drawbacks can include increased mechanical complexity, weight, and cost, especially for manual units with more shift forks, or for automatic units with additional gears.

Sixspeed transmissions are common in both cars and motorcycles. They are widely adopted in passenger cars, light trucks, and sport bikes, and in some segments are being complemented or replaced by seven- or eight-speed gearboxes, dual-clutch arrangements, or other advanced transmission technologies, depending on manufacturer and design priorities.

The term also appears in product names, marketing materials, and aftermarket parts. As a general descriptor, it is used to compare gear counts and transmission configurations across different vehicles and brands.