Progressive Shift - Detroit Diesel DDEC VI Application And Installation

5.22

PROGRESSIVE SHIFT

The Progressive Shift option offers a high range maximum Vehicle Limit Speed to encourage
the use of high (top) gear during cruise operation. Progressive Shift encourages the driver
to upshift from a lower to a higher gear prior to reaching the engine's governed speed. The
resulting lower engine speed in high range should result in improved fuel economy. Progressive
shifting techniques should be practiced by every driver, but can be forced if fleet management
considers it necessary. The benefits from progressive shifting are best realized during stop-and-go
driving cycles.
The rate of acceleration will be limited below the programmed MPH to encourage up shifting.
As the driver accelerates beyond a specified MPH speed, the rate of engine acceleration is limited
in higher RPM, to encourage (force) the operator to select the top gear.
□ Progressive Shift should be used with 2100 RPM rated engines in fleet applications where
the reduced driveability will not impede trip times or productivity.
□ Progressive Shift is not compatible with automatic transmissions.
NOTE:
Progressive Shift should be selected only when Spec Manager is run. Progressive
Shift selection without Spec Manager could result in mismatched equipment, poor
fuel economy, and poor performance. Your local Detroit Diesel Distributor will run the
program.
5.22.1 OPERATION
The Progressive Shift option has two sets of low ranges and one set of high range parameters,
which are programmable with DDDL 7.0, DRS, or VEPS. Refer to section 5.22.6. The example
shift pattern chart (see see Figure 5-27) reflects default values when the Progressive Shift option
is chosen and the low and high gear parameters are not modified.
All information subject to change without notice. (Rev. 01/07)
7SA827 0701 Copyright © 2007 DETROIT DIESEL CORPORATION
DDEC VI ELECTRONIC CONTROLS APPLICATION AND INSTALLATION
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