Kia details eight-speed auto

KIA has revealed details of its new eight-speed transmission that will slowly be rolled out to mid-size and larger front-wheel-drive models in its global arsenal.

The South Korean car-maker has already developed an eight-speed auto for use in larger rear-wheel-drive models but said in a release that producing the unit for use in front-drive cars was a challenge because of packing constraints, having to mount the transmission transversely and “competing with the engine, suspension and auxiliary components for space under the bonnet”.

The new front-wheel drive eight-speeder will make its debut in the 2017 Kia Cadenza, a left-hand-drive only model that has been ruled out for the Australian market. It will be used to drive the front wheels in Cadenza variants that are powered by a 3.3-litre V6 GDI petrol engine.

Kia says that the transmission will serve as a “stepping stone” in developing future “advanced” Kia transmissions.

While the car-maker has not specified which of its models the transmission will flow down to, likely Australian applications include the Optima mid-size sedan, Sorento and Sportage SUVs and the Carnival people-mover.

Each of those models are currently matched with a six-speed automatic transmission. It is unlikely that the new shifter will be used in smaller models such as the Cerato or Rio.

It is also believed that Kia will continue to roll out its seven-speed dual-clutch transmission for sportier models, meaning there is a good chance it will be fitted to the forthcoming rear-drive four-door sports sedan based on the GT concept that is rumoured to lob sometime next year.

Kia says the new transmission has been in development since 2012 and that there are 143 patents for new technologies to ensure “a high level of performance and efficiency in a compact structure”.

Engineers reduced the size of the transmission’s oil pump – the smallest oil pump of any transmission in its class according to Kia – and simplified the structure of the valve body in a bid to lower fuel use.

Quicker gear shifting was achieved by reducing the number of control valves from 20 to 12.

By having an extra clutch and gears compared with the six-speed unit, Kia has increased the ratio between the top gear and the lowest gear by 34 per cent aiding noise, vibration and harshness (NVH) levels in higher gears, while making for faster acceleration and climbing performance in low gears.