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Auto Retarder in Cruise
Description:
Auto Retarder in Cruise determines the miles per hour
(km/h) value above the cruise set speed that the engine
retarder will turn On. The Retarder switch must be in
the On position and cruise control set, for this feature
to operate. Programming the Auto Retarder in Cruise
parameter to 0 (zero) will disable the feature. This
parameter works in conjunction with the Auto Retarder
in Cruise Increment parameter. The initial braking level
(Low or Hi) of retarding is dependent on the value of the
Auto Retarder in Cruise Increment parameter.
45
55
65
Auto Retarder In Cruise
Programmed to 3 MPH
Cruise Set Speed
Example: The cruise speed is set at 55 MPH and Auto
Retarder in Cruise parameter is programmed to 3 MPH.
When the truck accelerates to 58 MPH, by going down
hill, the retarder will activate.
Available:
All electronically programmed on-highway engines
Range:
Engine
Range
Cat
DefaultMinimum Maximum
C-10, C-12, C-15,
C-16, C11, C13, C15
0 MPH
(0 km/h)
10 MPH
(16 km/h)
0 MPH
(0 km/h)
C7, C9
3 MPH
(5 km/h)
10 MPH
(16 km/h)
0 MPH
(0 km/h)
EPA’07 C7, C9, C13,
C15
0 MPH
(0 km/h)
10 MPH
(16 km/h)
0 MPH
(0 km/h)
Advantages:
Auto Retarder in Cruise can increase driver comfort and
reduce driver fatigue while maintaining the desired road
speed.
Note: The maximum Retarder level is determined by the
Retarder Level switch position.
Disadvantages:
Programming this parameter to a speed that is too
low can result in a degraded fuel economy. See
Recommendations and the Auto Retarder in Cruise
Increment parameter discussion to avoid this effect.
Cruise Control Parameters