Peterbilt 325 2017, Operator'S Manual

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AXLE
Dual Range (Two-Speed)
Rear Axle
Your vehicle may be equipped with a
two-speed or dual range axle (option).
You can select two rear axle ratios for
operating under heavy loads or rough
terrain as well as for over the road
hauling.
The Low Range provides maximum
torque for hauling heavy loads or
traveling over rough terrain. The High
Range is a faster ratio for highway
speeds and general over the road
conditions. A switch on the accessory
switch panel controls the Dual Range
Rear Axle. You will notice that the
switch has a guard to protect you from
activating it accidentally. Always park
your vehicle with the range selector in
LOW.
Dual Range Axle Operation
Important tips on operating a Dual
Range Axle with Interaxle Differential:
Shift the axle with the inter-axle
differential in the unlocked position
only.
When you are driving with poor
traction, lock the differential. When
you have the differential locked, drive
with the axle in LOW range only.
When you are driving on a surface
with good traction, keep the interaxle
differential unlocked. You can drive
with the axle in the LOW or HIGH
range.
Always UNLOCK the inter-axle
differential before shifting the axle
speed range.
CAUTION
If you shift the axle range with the
inter-axle differential in LOCK, you
could seriously damage the axles.
Never shift the axle range with the
differential locked.
4-48
Y53-6060-1C1 (03/17)
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