Peterbilt Medium Duty Trucks Operator's Manual after 1-07

Operating Instructions
OPERATING THE REAR/DRIVE AXLE
Introduction
This section covers the operation of your Rear/Drive Axle.
These instructions apply to the most common features of
drive axles. Refer to the manufacturer’s instructions for further
information on the operation of your axle.
If your vehicle is equipped with a Rockwell Tractech Nospin
single rear axle, the wheel differential lock feature automatically
engages and disengages. When one wheel starts
to spin on a slippery surface, this rear axle feature engages
to improve traction.
Operating the Rear/Drive Axle
When operating normally on paved, dry surfaces, keep your
truck's interaxle differential in the UNLOCK position.
GUARD
Interaxle Differential Lock Switch in normal (unlocked)
position
Interaxle Differential Lock
On vehicles with tandem rear axles, the interaxle differential
allows each axle to turn independently. Differential action
between the tandems relieves stress on the rear axles and
reduces tire wear. The interaxle differential lock switch allows
the operator to LOCK or UNLOCK the differential, depending
on road surface conditions.
Interaxle Differential Lock Switch in locked position
Medium Duty (R10/06) Y53-6008 – 95 –