freightliner Run Smart ARGOSY, Driver Manual

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Differential Lock
The driver-controlled differential lock feature (side-to-
side wheel lock, traction control, or traction equalizer)
provides maximum traction for slippery conditions by
forcing the wheels on each drive axle governed by
the switch to rotate together. When the differential
lock is engaged, the clutch collar completely locks
the differential case, gearing, and axle shafts to-
gether, maximizing the traction of both wheels.
Differential Lock Switches
There are several differential lock options available:
•
a switch to control the differential lock on the
forward drive axle.
•
a switch to control the differential lock on the
middle drive axle.
•
a switch to control the differential lock on the
rearmost drive axle (see
Fig. 16.1 , Item 3).
Differential Lock Operation
NOTE: On some vehicles, the differential lock
system is connected through the low speed
range of the transmission. If this system is used,
the transmission must be in the low speed
range for the wheels to fully lock. In addition,
shifting out of low speed range will also disen-
gage the differential lock.
WARNING
Locking the wheels when the vehicle is traveling
down steep grades or when the wheels are slip-
ping could damage the differential and/or lead to
loss of vehicle control, causing personal injury
and property damage.
NOTICE
Engage the differential lock only when the ve-
hicle is stopped or moving at less than 5 mph (8
km/h). Engaging the differential lock at high
speeds can cause internal axle damage.
1. With the engine running, move the differential
lock switch to LOCK to engage the differential
lock.
2. If the vehicle is moving, briefly let up on the ac-
celerator to relieve torque on the gearing, allow-
ing the differential to fully lock.
WARNING
Be especially careful when driving under slippery
conditions with the differential locked. Though
forward traction is improved, the vehicle can still
slip sideways, causing possible loss of vehicle
control, personal injury, and property damage.
3. Drive cautiously and do not exceed 25 mph (40
km/h). When the differential is fully locked, the
turning radius will increase because the vehicle
understeers. See
Fig. 16.2 .
1
2
3
4
01/05/2012 f611158
1. Interaxle Lock Switch
2. Fifth Wheel Slide Switch
3. Rearmost Axle Differential Lock Switch
4. Air Suspension Dump Control Switch
Fig. 16.1, Axle and Suspension Switches
Drive Axle Feature Operation
16.1