Peterbilt 579 - U-Bolt Torque

FRONT AXLE AND SUSPENSION
U-Bolt Torque
It is important that U-bolts remain tight.
Severe use of your vehicle will cause
them to loosen faster. But all vehicles
need to have their U-bolts checked and
tightened regularly. Be sure someone
with the proper training and the right
tools checks and tightens the U-bolts
on your vehicle.
New springs
can settle in after service,
relieving the tension on the U-bolts.
Loose U-bolts can cause leaf spring
breakage, axle misalignment, hard
steering and abnormal tire wear.
All vehicles
should have suspension
U-bolts tightened after the rst 500
miles (800 km) of operation. Re-torque
the front spring pinch bolts and shackle
pinch bolts.
Do not operate the vehicle if the
U-bolts are not properly tightened.
Loose U-bolts will cause the axle to
not be properly secured to the sus
-
pension, which could cause loss of
vehicle control and an accident. Loose
U-bolts can also cause uneven tire
wear and poor alignment. Failure to
comply may result in death, personal
injury, equipment or property damage.
WARNING!
U-bolts are difcult to tighten unless
you have the right equipment. If you
cannot tighten them correctly yourself,
be sure to have them checked and
tightened regularly by an authorized
mechanic.
Tighten
U-bolt nuts to the specied
torque value with the vehicle loaded to
its normal gross weight. The following
torque values apply to U-bolts and
nuts with clean threads lubricated with
Chevron zinc
lubricant (SAE 20 or 30
oils acceptable but not preferred).
WARNING!
Do not replace U-bolts and nuts with
common U-bolts or standard nuts.
These parts are critical to vehicle
safety. If the wrong U-bolts or nuts
are used, the axle could loosen or
separate from the vehicle and cause
a serious accident. Use only U-bolts
and nuts of SAE Grade 8 specication
or better. Failure to comply may result
in death, personal injury, equipment or
property damage.
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(04/13) Y53-6047–2C 5-109