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Engine/Gear Parameters
Gear Down Protection RPM Limit
OEM
FORMERLY - HIGH GEARS ENGINE RPM LIMIT
Gear Down Protection Turn On Speed
OEM
FORMERLY - HIGH GEARS TURN ON SPEED
Description:
Gear Down Protection allows you to set an engine rpm
limit for the higher gears that ensures cruising speed
can only be reached in top gear.
Gear Down Protection has two parameters to specify.
The fi rst is the Gear Down Protection Turn On Speed.
This is the point, in either mph or km/h, where the RPM
limit fi rst takes effect. In the illustration below the Gear
Down Protection Turn On Speed is set at 45 MPH. The
second parameter is the Gear Down Protection RPM
Limit. It is set at 1600 rpm in the illustration.
With some driveline combinations cruising speed can
only be reached while in the transmission’s top gear; the
Gear Down Protection RPM Limit would not have to be
set for these trucks
0 10203040506070
1000
1200
1400
1600
1800
2000
Peak
Torque
VSL
HCC
TEL
LCC
Intermediate
Gears
Lower
Gears
PTO
VSL
MPH
RPM
It is important to note that although Low/Intermediate
Gears parameters are “soft” limits, Gear Down
Protection is actually a “hard” limit.
Available:
All electronically controlled on-highway engines
covered in this handbook
Range:
Gear Down Protection RPM Limit
Engine
Range
Cat
Default
Minimum Maximum
C-10, C-12, C-15, C-16,
C11, C13, C15
1300 RPM TEL TEL
3126E, C7, C9 1700 RPM TEL TEL
EPA’07 and newer C7,
C9, C13, C15
1300 RPM TEL TEL