Debuts on the 2017 Cadenza.

Developed in-house by Kia’s engineers, the new eight-speed automatic gearbox has just about the same size as the company’s six-speed auto but it weighs 7.7 pounds (3.5 kilograms) less. Work on the new transmission kicked off back in 2012 and led to no less than 143 patents registered by the South Korean marque which promises not only a boost in efficiency, but also lower noise, vibration, and harshness (NVH) levels.

Kia already had experience with an eight-speed auto for RWD cars, but engineering an 8AT to cater FWD cars was trickier taking into account it had to be mounted transversely without taking up a lot of space. As such, the size of the oil pump has decreased compared to the six-speed auto and Kia says it’s actually the smallest oil pump developed for a transmission in its class. The company goes on to specify the new unit can use the hydraulic oil in a more efficient way by distributing it evenly at all times throughout the ‘box.


Moreover, the newly developed 8AT has a simplified valve body with only 12 valves (down from 20) thanks to the re-engineered direct control valve body which allows solenoid control of the clutch directly instead of requiring several control valves. As a result of the changes, Kia emphasizes gear shifts are now faster than before and the extra clutch and the two additional gears over the 6AT have enabled a ratio increase of 34 percent between the lowest gear and the highest one. The hardware changes will also pay dividends in terms of fuel economy as well as enable lower NVH levels during acceleration and in higher gears.

The first model to make use of the eight-speed, dual-clutch automatic is the 2017 Cadenza which we drove just last month. Paired with the new biturbo 3.3-liter V6 engine, we found the transmission to be silky smooth up to the point you can barely notice when it changes gears.

The 2017 Cadenza is only just the tip of the iceberg, with Kia saying the 8AT will also be implemented in several midsize and fullsize FWD models in the future.

Source: Kia

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Kia new eight-speed automatic transmission for FWD cars

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Kia Introduces its First Front-Wheel Drive Eight-Speed Automatic Transmission

  • Advanced transmission developed in-house for front-wheel drive models
  • Intelligent packaging ensures lighter weight and similar dimensions as a conventional six-speed automatic transmission
  • 143 new patents filed throughout development of advanced transmission
  • Eight-speed FWD automatic transmission to debut in 2017 Kia Cadenza
(SEOUL) September 6, 2016 – Kia Motors has revealed details of its advanced new eight-speed automatic transmission (8AT), engineered for use in front-wheel drive vehicles.
 
Kia’s new front-wheel drive 8AT (FWD 8AT) has been developed in-house by the Korean manufacturer, engineered to offer a high level of mechanical efficiency and smooth gearshifts. Crucially, the new FWD 8AT occupies the same space as a conventional six-speed automatic transmission, and weighs 3.5 kg less.
 
Kia’s engineers already have experience of developing eight-speed transmissions for rear-wheel drive vehicles, mounting the transmission longitudinally and sending power to the rear axle. However, incorporating the same number of gears into a front-wheel drive car is incredibly challenging, due to packaging constraints and the need to mount the transmission transversely, competing with the engine, suspension and auxiliary components for space under the bonnet.
 
Intelligent packaging and 143 new patented technologies
Under development since 2012, the development program for the breakthrough transmission led Kia to patent 143 new technologies to ensure a high level of performance and efficiency in a compact structure. This new transmission enables smooth acceleration from standstill, as well as greater fuel efficiency, improved NVH characteristics, and more decisive acceleration at high speeds than an automatic transmission with fewer gears.
 
To improve the 8AT’s fuel economy, Kia engineers significantly reduced the size of the oil pump (the main source of power loss in an automatic transmission) and simplified the structure of the valve body. Boasting the smallest oil pump of any production transmission in its class, the 8AT is able to use hydraulic oil more efficiently, distributing it evenly throughout the unit at all times.
 
Kia’s development teams also incorporated a direct control valve body to allow solenoid control of the clutch directly, rather than via several control valves. This enabled Kia to reduce the number of control valves from 20 to 12, resulting in quicker gear shifts, a more direct mechanical link to the engine and improved packaging.
 
Incorporating an additional clutch and gear over Kia’s existing 6AT, the ratio between the top gear and the lowest gear in the new transmission has been increased by 34% over the 6AT, resulting in greater fuel economy and improved NVH in higher gears and faster acceleration and climbing performance in low gears.
 
Transmission to debut in all-new 2017 Kia Cadenza
Kia’s new front-wheel drive 8AT is making its global debut in the 2017 Kia Cadenza – on sale across selected global markets this year – and is featured as standard on Cadenza models powered by the 3.3-liter V6 GDI engine.
 

Going forward, Kia’s new eight-speed automatic transmission will be applied to a number of mid-sized and larger front-wheel drive models, and will serve as a stepping stone to the development of future advanced Kia transmissions.