operators_manual

However, suspensions in over-the-road
operations require periodic inspection to
ensure trouble-free performance.
WARNING
Do not work on the vehicle without the
parking brake set and wheels blocked
securely. If the vehicle is not secured
to prevent uncontrolled vehicle move-
ment, it could roll and may result in
death, personal injury, equipment or
property damage.
WARNING
Do not operate the vehicle if the sus-
pension U bolts are not properly tight-
ened. Loose U bolts will cause the
axle to not be properly secured to the
suspension, 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
Failure to maintain the specified torque
values or to replace worn parts can
cause component system failure, pos-
sibly resulting in an accident. Improp-
erly tightened (loose) suspension U
bolts can lead to unsafe vehicle condi-
tions, including: hard steering, axle
misalignment, spring breakage or ab-
normal tire wear. Failure to comply
may result in death, personal injury,
equipment or property damage.
CAUTION
DO NOT spray the suspension with
chemical products or mineral oil; it can
cause damage to the bushings.
NOTE
Failure to follow these recommenda-
tions could void warranty.
Visual Inspection
For all vehicles, mandatory maintenance
procedures include retightening of U-bolts
and complete inspection. However, even
with proper maintenance, many factors
affect the service life of springs and
suspension components, such as: fatigue,
vehicle gross weight, type of load, road
conditions, and vehicle speed. It is
important that U-bolts remain tight. Severe
use of your vehicle can 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. After
the first 500 miles (800 km) of operation,
inspect the suspension periodically, as
noted below:
• Visually check for loose or missing
fasteners, cracks in hanger, or axle
connection brackets.
• Check that springs are centered in
hangers and in good condition.
• Check for cracks, wear marks,
splits, or other defects on the
surface of the spring.
• Replace defective parts. Because
repaired springs cannot be fully
restored to their original service
MAINTENANCE - Rear Axle and Suspension
256 Y53-6047-2HEN (03/18)
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