London bus trial confirms fuel savings after retrofitting Allison’s xFE transmission

Alexander Dennis Limited (ADL) backs UK customer transmission upgrade programme following Go Ahead London’s up to 7.13% fuel saving on an ADL Enviro200 midibus.

LONDON, October 17, 2019 – Real-world trials of a midibus retrofitted with Allison’s xFE transmission hardware and FuelSense® 2.0 software are showing fuel economy improvements of up to 7.13%, and an average across seasons of 4.37%. The 15-month study demonstrates the financial savings achievable when mid-life bus upgrades include the adoption of Allison’s transmission package.

The trial, which started in August 2018 and is ongoing, has measured fuel consumption during the daily working routine of an ADL Enviro200 bus equipped with an Allison T 2100 transmission. The tests have been conducted independently of Allison by Go-Ahead London, the largest bus company in the capital, and ADL, the UK’s biggest bus and coach manufacturer. As a result of the consistent findings over a 15-month period, ADL has formulated an upgrade programme for UK customers running Allison Transmissions.

The Enviro200 operates out of Go-Ahead’s Stockwell depot where it has covered approximately 2,400 miles per month since being added to the fleet in 2013. Fuel consumption was initially measured without xFE hardware installed and with Allison’s first-generation FuelSense software, before measuring again after fitting xFE and the latest FuelSense 2.0 software. It has been proven, after 36,000 miles of testing, that updating the transmission technology in this way can cut fuel bills on this route by up to £2,000 per bus per year. If Go-Ahead retrofitted xFE and FuelSense 2.0 to each of the 14 London buses in that depot equipped with an Allison T 2100 transmission, it could cut fuel costs by £28,000 and save approximately 27,860 kg of CO2 per year.

Richard Harrington, Go-Ahead London Engineering Director, commented: “This was a realistic and rigorous trial on the roads of one of the world’s busiest cities. We were interested to see how, through configuration of the transmission software, operators can choose their own balance between fuel economy and performance, and we were impressed by the fuel savings.”

Allison’s latest fully automatic bus transmission is named xFE because it delivers extra fuel economy in addition to the fuel savings obtained through Allison’s FuelSense features. xFE incorporates a newly designed torque converter lockup clutch enabling 1st gear lock up at low speeds coupled with FuelSense 2.0 technology, making the T 2100 xFE ideally suited for transit and city buses.

Allison’s FuelSense 2.0 software features Neutral at Stop and coast coupled with DynActive™ Shifting. This employs a real-time learning algorithm which finds the ideal balance of fuel consumption and performance by automatically adjusting the transmission control to the load, speed and topography.

ADL is encouraging all of its customers who currently have Allison transmissions to consider installing Allison’s xFE transmission and FuelSense 2.0. This work can be done at ADL premises and at Allison dealerships, but in the first instance, interested bus operators are advised to contact ADL directly.

Claire Dumbreck
Propel Technology
+44 (0)1295 770868
Unit 4, Manor Farm Offices
Northend Road, Fenny Compton
Warwickshire, UK

Miranda Jansen
Allison Transmission Europe
Marketing Communications
+31 (0) 78 6422 174
Baanhoek 118
Sliedrecht, The Netherlands

Oct 18, 2019


Allison Transmission (NYSE: ALSN) is a leading designer and manufacturer of vehicle propulsion solutions for commercial and defense vehicles, the largest global manufacturer of medium- and heavy-duty fully automatic transmissions, and a leader in electrified propulsion systems that Improve the Way the World Works. Allison products are used in a wide variety of applications, including on-highway trucks (distribution, refuse, construction, fire and emergency), buses (school, transit and coach), motorhomes, off-highway vehicles and equipment (energy, mining and construction applications) and defense vehicles (tactical wheeled and tracked). Founded in 1915, the company is headquartered in Indianapolis, Indiana, USA. With a presence in more than 150 countries, Allison has regional headquarters in the Netherlands, China and Brazil, manufacturing facilities in the USA, Hungary and India, as well as global engineering resources, including electrification engineering centers in Indianapolis, Indiana, Auburn Hills, Michigan and London in the United Kingdom. Allison also has more than 1,400 independent distributor and dealer locations worldwide. For more information, visit