Load Based Shift Schedule Dynamic Shift Sense Allison Transmission Load Based Shift Schedule Dynamic Shift Sense

Load Based Shift Schedule Allison responded to customer demands of fuel economy by tailoring their 5th generation shift controls to offer variable shift points and lower the engine RPM Freightliner specs default to “medium” which is a mix of performance and economy shift points The economy shift points cause issues in some applications particularly with ISB engines by upshifting at low RPMs Typical complaint is “low power” and many of these trucks have had extensive engine side investigations trying to resolve the performance complaints

Load Based Shift Schedule Cummins ISB is a 2600 RPM no load engine (2400 RPM full load) Cummins recommends a performance cruise RPM of 2150 to 2400 RPM Cummins recommends an economy cruise RPM of 1700 to 1900 RPM That’s a 400 to 500 RPM spread between those two points!

Load Based Shift Schedule The economy setting on Load Based Shift Schedule drops the shift point by about 400 to 500 RPM and can cause an upshift to the next gear at or below the peak torque RPM Acceleration on a freeway on-ramp suffers greatly in this mode Some customers have complained of safety with this calibration Full power downshifts don’t occur until we lose considerable road speed resulting in a lower speed up the hill

Load Based Shift Schedule We have the capability to program the LBSS to a more aggressive shift pattern Whittier has the software and Pat has the software to make these changes This program has corrected the performance complaints in every instance that we have encountered Fuel economy may degrade slightly, but most ISB customers do not track fuel economy, so the change is negligible

Dynamic Shift Sense/ Fuel Sense Allison’s new program that combines the features of LBSS with other fuel economy features The most fuel efficient versions of Dynamic Shift Sense offer auto neutral at idle, ECO Cal with super low shift points and acceleration rate management that controls engine torque. These features offer benefits to those customers who are very aggressive in their fuel economy efforts These features can cause a lot of grief in the wrong applications

Dynamic Shift Sense/ Fuel Sense If you are specing new trucks with Allison Transmission, get Bob Chamberlin involved in helping you to make the right choices DTNA will default to a generic spec, but many choices are available: 84L-003 High Dynamic Shift Sense Low Acceleration rate mgmt. 84L-006 Medium Dynamic Shift Sense Low Acceleration rate mgmt. 84L-007 Low Dynamic Shift Sense High Acceleration rate mgmt. 84L-008 Low Dynamic Shift Sense Medium Acceleration rate mgmt. 84L-009 Low Dynamic Shift Sense Low Acceleration rate mgmt. 84L-013 Low Dynamic Shift Sense Disable Acceleration rate mgmt