SOUTH KOREA: Details of new transmission for next Hyundai Sonata Hybrid

By Glenn Brooks | 28 October 2014

Hyundai Motor has announced the first details of a new six-speed automatic transmission for its future hybrid cars.

The new gearbox was revealed earlier on 28 October at the company's annual International Powertrain Conference held in Namyang (South Korea). 

Hyundai says the new six-speed automatic transmission's main innovation is the integration of the electric motor. The new unit will be fitted to future Hyundai hybrids, including the next petrol-electric Sonata.
According to the firm, almost all of the hybrid powertrain components are contained within the transmission, thus minimising energy losses and increasing fuel economy. A new traction motor and electric oil pump (EOP) are fitted, while the torque converter has been removed. A lighter torsion damper, and new engine clutch, which features fewer clutch discs, are claimed to reduce drag and contribute to a more efficient transfer and use of power.
The new transmission with the new oil pump system is said to achieve improved fuel efficiency by replacing the mechanical oil pump with an electric one, thereby eliminating hydraulic losses.
With fewer components, the new transmission is claimed to weigh 130kg (wet) – making it lighter than its previous version – yet still delivers 280Nm (28.5 kg.m) of torque.