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

Vehicle Recovery and Spring Brakes
push rod) is retracting. Do not over-torque the release
stud assembly. (S–Cam type maximum: 50 ft-lb, Wedge
type maximum: 30 ft-lb.) The spring brake is now
mechanically released.
Freeing the Vehicle from Sand,
Mud, Snow and Ice
WARNING! Do not spin the wheels faster
than 35 mph (55 km/h). Spinning a tire at
speedometer readings above this can be
dangerous—tires can explode from spinning
too fast. Under some conditions, a tire may
be spinning at a speed twice that shown on
the speedometer. Any resulting tire explosion
could cause severe injury or death to a
bystander or passenger, as well as extensive
vehicle damage: including tire, transmission
and/or rear axle malfunction.
If the vehicle gets stuck in sand, mud, snow, or ice:
• Move the gearshift lever or selector from First to
Reverse.
Operating Instructions
• Apply light pressure on the accelerator pedal while the
transmission is in gear.
• Remove your foot from the accelerator while shifting.
• Do not race the engine.
• For best traction and safety, avoid spinning the wheels.
Comply with the following instructions to avoid transmission
damage:
• Always start the vehicle in motion with the shift lever in
first gear.
• Be sure that the transmission is fully engaged in gear
before releasing the clutch pedal (manual only).
• Do not shift into reverse while the vehicle is moving.
• Do not permit the vehicle to be towed for long distances
without removing the driveshaft.
Tire Chains
If you need tire chains, install them on both sides of the driving
axle.
CAUTION: Chains on the tires of only one tandem
axle can damage the driveline U–joints and
the interaxle differential. Repairs could be costly
and time-consuming.
– 112 – Y53-6008 Medium Duty (R10/06)