Allison Transmission fulfils fuel saving promise
Allison Transmission has delivered on a promise of fuel saving from its xFE fully automatic transmissions after trials on a pair of refuse collection vehicles showed diesel consumption reduced by almost five percent. CVW takes a look.
Introduced to the European medium-duty truck market in June 2021, the 3000 xFE and 3200 xFE transmissions differ from their standard counterparts allowing early lock up in first gear versus second gear. The double overdrive ratios in the fifth and sixth gears are also optimised, resulting in an improved ratio spread of 11%.
These new features target improvements in fuel economy and exhaust particulates. Earlier lock up reduces transmission power losses from the torque convertor, reducing heat from the powerpack and allowing the truck’s engine to operate at lower rpm for a given road speed. The optimised overdrive gears reduce the engines cruise rpm for further fuel consumption and exhaust emissions improvements.
Many refuse trucks operate in low-speed urban areas where air quality is at its most critical. The xFE series is designed to help address these ongoing concerns and improve operators’ return on investment. Further fuel savings come from Allison’s FuelSense 2.0 software and electronic control system, which is installed as standard on the xFE transmissions.
Carbon and fuel reduction
The advantage has most recently been demonstrated via a 12-month UK trial incorporating 24 months of data, involving removing the standard Allison transmissions from two Dennis Eagle Elite 26-tonne trucks operated by Biffa on commercial waste collection duties and replacing them with the xFE equivalents.
Operating on identical routes throughout the West Midlands and the Wirral, and on a variety of duty cycles, the trucks with the Allison xFE transmissions returned an average fuel saving of 4.8% compared with their previous performance.
The results support the theoretical CO2 emissions saving calculated using the European standard VECTO fuel consumption tool of up to 3.7% on the municipal utility cycle when compared to the Allison 3000 Series close-ratio transmission. This provides an essential carbon reduction option for vehicles within fleets that may be unsuitable for EV alternatives at the current time.
“These compelling results are supported by telematics data from DE Connect, providing CANbus information instantaneously for componentry functionality, vehicle fuel usage, and real-time vehicle tracking information, Allison iSCAAN data gathering and analysis tool, and finally our own in-house telemetry engineering system, “explains Nathan Wilson, account and area sales manager UK & Republic of Ireland, Allison Transmission.
“All systems aligned, showing fuel savings from the earlier lock-up in first gear. Achieving this reduces the time the transmission spends in lower gears, rather than torque-converter mode and allows engine speeds to be reduced by 400 rpm at the lock-up point. The xFE’s gear ratios in fifth and sixth are faster than those in the standard Allison transmissions, allowing greater efficiency at higher speeds and lower rpm, again reducing fuel consumption.”
“Biffa is committed to driving sustainable innovation across all its operations and we are proud to be involved in another successful partnership with Allison Transmission,” adds Steve Cole, Biffa’s group fleet and procurement director. “We provided historical data from our telematics system, operated the vehicles on identical routes over a 12-month period and installed additional telematics to validate the findings, which showed material fuel and carbon savings.”
