Metrocity with Allison xFE transmission and diesel engine offers a more affordable route to Low Emission Bus certification
25th January 2017

Latest list of LEB-accredited buses shows diesel can be a route to lower emissions; UK bus fleets can now specify an Allison transmission and qualify for LEB grants

 AMPTHILL, UK – The new Optare Metrocity xFE midi-bus has been added to the list of Low Emission Bus (LEB) accredited vehicles. Propelled by a Mercedes 5.1-litre four-cylinder turbo-diesel engine and Allison’s latest T3270R xFE™ transmission, the bus delivers significant reductions in fuel consumption and tailpipe emissions.

“Optare continually strives to offer buses that not only improve air quality in our towns and cities but also offer operators the lowest whole life costs,” said Robert Drewery, commercial director for Optare. “The Metrocity has been extremely well received since its launch in 2012 and has been praised by our customers for its fuel efficiency.”

The Metrocity xFE model, which debuted in November, presents UK bus operators with a more affordable way of achieving LEB certification than investing in new engine-power technologies such as electricity, hydrogen fuel cells, or biomethane.

Allison’s xFE transmissions feature the latest advances in fuel-saving technology. All four new variations of the xFE range offered in Europe – T3270 xFE™, T3280 xFE™, T3325 xFE™ and T3375 xFE™ – incorporate optimized gear ratios coupled with the FuelSense® Max package. Designed to deliver significantly more lock-up operation, they operate at lower engine speeds in higher ranges for further fuel economy improvements. During independent tests conducted under conditions representative of actual service, the Euro 6 Metrocity with the T3270 xFE transmission and FuelSense® Max delivered a fuel economy improvement of 8 percent over the previous model.

“Working in partnership with suppliers such as Allison to develop buses such as the Metrocity xFE enables Optare to continue to lead the way in reducing whole life costs for operators,” said Drewery.

To be accredited as a LEB, a vehicle must achieve a reduction of more than 15 percent in well-to-wheel greenhouse gas emissions (methane, carbon dioxide and nitrous oxide) compared with a Euro 5 diesel bus, and must meet the Euro 6 engine standard in other emissions. Euro 6 has brought a dramatic improvement in the environmental friendliness of conventional diesel engines, delivering a 95 percent reduction in emissions of nitrogen oxides compared with previous Euro 5 models.

The LEB standard was introduced in 2015 as successor to the Low Carbon Emission Bus (LCEB) certification initiated in 2008. Defined by the Low Carbon Vehicle Partnership (LowCVP) on behalf of the Office for Low Emission Vehicles (OLEV) and Department for Transport, this standard is a key part of the drive to reduce greenhouse gas emissions from UK bus fleets and to improve local air quality. Greener transport is seen as key to helping towns and cities meet European clean air targets, which are currently being breached in 38 of 43 UK zones.

High res image of Optare Metrocity xFE midi-bus

High res image of Optare Metrocity xFE midi-bus side on view

About Allison Transmission

Allison Transmission (NYSE: ALSN) is the world’s largest manufacturer of fully automatic transmissions for medium- and heavy-duty commercial vehicles and is a leader in hybrid-propulsion systems for city buses. Allison transmissions are used in a variety of applications including refuse, construction, fire, distribution, bus, motorhomes, defense and energy. Founded in 1915, the company is headquartered in Indianapolis, Indiana, USA and employs approximately 2,700 people worldwide. With a market presence in more than 80 countries, Allison has regional headquarters in the Netherlands, China and Brazil with manufacturing facilities in the U.S., Hungary and India. Allison also has approximately 1,400 independent distributor and dealer locations worldwide. For more information, visit