just-auto.com

Allison launches nine-speed autobox, expands electrification

By Graeme Roberts | 20 September 2018

Allison Transmission said it would offer its medium-duty, fully automatic nine-speed transmission worldwide, adding it had developed an electric hybrid system with purely electric extended range.

The news was revealed at the 67th IAA Commercial Vehicles show.

The supplier claims the new transmission provides significant fuel savings as the efficient gear train allows the torque converter to lock up early in first gear. It includes an optional integral engine stop-start system that provides immediate transmission engagement and vehicle hold while the engine is restarted. It is recommended for distribution trucks, rental and lease trucks, and school buses.

The nine speed version builds on claimed proven durability of the 2000 Series six speed transmissions which have accumulated more than 100bn miles globally. It's been designed to use the same vehicle manufacturers interfaces as its predecessor, providing ease of integration into vehicles currently fitted with the 2000 Series.

Allison now offers an electric hybrid system with a purely electric extended range of up to 15km or about 10 miles. It said this is ideal for transit bus and motor coach applications with zero-emissions engine off on approaching, during and leaving passenger stops.

A li-ion battery extends engine off range, a smaller, lighter dual inverter with water ethylene glycol cooling is more efficient and Increased Power Accessory II improves fuel economy by using the hybrid system to power accessory components like air conditioning, air compressors and power steering.

Battery charging is accomplished via regenerative braking and engine operation. The regenerative braking capability can extend the brake change interval by up to 350%, it is claimed. |Two-mode split parallel architecture improves fuel economy up to 25%.