Kia Launches Front-Wheel-Drive 8-Speed Transmission

Kia Motors Corp. has developed an 8-speed automatic transmission for front-wheel-drive vehicles. The gearbox debuts this autumn in the 2017 Cadenza full-size sedan.

Kia, which already offers 8-speed automatic transmissions for rear-drive powertrains, says it received 143 patents for the fwd gearbox that has been in development since 2012.

A fwd unit is transversely mounted and has more packaging constraints due to its proximity to the engine and suspension components than longitudinally mounted rwd transmissions. Kia says it used a lightweight design that allows the 8-speed transmission to fit in the same space as a conventional 6-speed automatic while reducing weight by nearly 8 lbs.

The 8-speed transmission is smoother and improves fuel efficiency, NVH and acceleration compared with 6-speed systems, Kia says. The design includes what’s described as the smallest oil pump in its class to further bolster fuel economy.

A simplified valve body enables direct solenoid control of the clutch, which Kia says allowed it to reduce the number of control valves from 20 to 12. This provides quicker gear shifts, a more direct mechanical link to the engine and improved packaging.

Incorporating an additional clutch, the 8-speed’s overall gear ratio has been increased 34% compared with a 6-speed unit.