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Disadvantages:
This setting provides minimal fuel savings for long
haul operations unless the driver stops frequently and
regularly tries to “wind it up”.
Recommendations:
✔ Each of these parameters should be left at the
factory default value when using an Automatic
Transmission, with the exception of Eaton Top 2.
Lower Gears Limit
✔ Set the Lower Gears Limit no lower than Peak
Torque rpm + 200 rpm. Properly setting this
parameter requires a close look at many factors,
including engine rating, terrain and application.
For example, heavy-duty engines are typically set
at the following:
1200 rpm + 200 rpm = 1400 rpm
Note how Lower Gears and Intermediate Gears setting
fi t in the total spec, especially in respect to Top Engine
Limiting (stair step effect).
0 10203040506070
1000
1200
1400
1600
1800
2000
Peak
Torque
VSL
HCC
Gear Down RPM
TEL
LCC
Intermediate
Gears
Lower
Gears
PTO
VSL
MPH
RPM
Gear Down
Speed
A similar graph would apply to mid-range engines.
Intermediate Gears Limit
✔ Set the Intermediate Gears Limit halfway between
the Lower Gears RPM Limit and Top Engine Limit.
For example, the C-15 is typically set to the
following:
Lower Gears Limit = 1400 rpm
Top Engine Limit = 2120 rpm
Intermediate Gears Limit = 1760 rpm
Lower Gears and Intermediate Gears Limits
✔ Use Cat
®
Design Pro program to determine the
most effective setting for your application.
Note: Turn Off Speeds are automatically calculated in
the Cat® Design Pro computer program. Cat® Design
Pro is the easiest tool to use to build an effective spec.
Engine/Gear Parameters