INDIANAPOLIS — Allison Transmission Inc., a provider of medium- and heavy-duty commercial transmissions, is widening its ongoing product optimization initiative with new features for 2011.

All Allison 2011 automatic transmission models are available with new economy shift schedules for greater fuel economy.

For school buses, Allison 1000/2000 Pupil Transport/Shuttle Series models are available with increased torque converter lockup. Lockup occurs when the torque converter achieves a direct connection between the engine and the transmission. Allison’s new increased lockup enables the transmission to shift into lockup in first range and stay locked up through the higher range. Locking the converter earlier further assists in achieving improved fuel economy and vehicle performance.

Moreover, Allison 2nd Reverse is now an available option for the Oil Field Series 4700 model. 2nd Reverse offers a second “deep reverse” in addition to the standard reverse. It provides more maneuverability when operating in confined spaces and slow creep capability with high engine speeds, company officials said.  

Finally, Variable Modulated Main (VMM) is now featured with all Allison 3000/4000 models. VMM modulates the pressure required in the internal lubrication system to increase transmission efficiency and improve fuel economy. Allison 3000/4000 models are also available with new Low Speed Grade Assist to provide improved performance and reduced heat generation when climbing grades.