2021 Forte GT w/GT2, Currant Red, Wagner-Tuning Intercooler, Evilla Exhaust, Takeda S1 Intake
Compared to the 5-speed, the 6-speed automatic transmission applied to the new Sorento in Korea, for example, has 62 fewer parts, is 41mm shorter in length and 12kg lighter in weight, making it the most compact 6-speed transmission currently available. It produces a 10% improvement in fuel economy (14.1km/ℓ), 14% faster zero to 100km/h acceleration time (10.0 sec.) and 24% quicker 60km/h to 100km/h passing performance (5.0 sec.) (based on the Sorento diesel R-2.2 2WD).
The Theta 6-speed transmission for gasoline engines delivers an impressive 10.9 sec. acceleration time, 5.9 sec. passing performance and 10.7km/ℓ fuel economy.
What’s the difference between the previous 5-speed automatic and 6-speed automatic transaxle?
The new transmission provides better ride and acceleration during high-speed driving. The extra gear provides better balanced performance during driving, thereby reducing the impact of shifting gears to deliver a more comfortable ride and quicker acceleration.
Fuel economy has been greatly enhanced. The extra gear means the engine doesn’t have to work as hard at high speeds, and thereby reducing fuel consumption.
For these reasons, the 6-speed transmission was previously only applied to premium lines like the Mohave (Borrego).
What are some of the key new technologies applied to the 6-speed automatic transmission?
The unique layout with three planetary gearsets and an ultra flat torque converter shorten the unit’s overall length by 12mm. Four pinion differentials improve durability while the hydraulic deviation adjustment valve body enhances shift quality. The low-viscosity automatic transmission fluid (ATF) and torque converter slip lock-up raise fuel efficiency.
In particular, the application of ATF and elimination of ATF level gauge (dipstick) reduces the need for maintenance and leads to further savings for customers. (KIA did mention that they may use ZF-LifeGuard. Not positive if they did for sure).
What is the future application plan of the 6-speed automatic transmission?
The front-wheel drive 6-speed automatic transmission that was developed with 100% proprietary technology will be also applied to other Kia models, including the Opirus (Amanti) and Grand Carnival (Sedona).
This is a negative for me...seriously I hate GM autotrannys because they do not have a dipstick and fluid changes are a PAIN. I like to check the tarnny's fluid color, condition and smell when I change the engine oil! Makes no sense -- why not get rid of the engine's oil dipstick too?