operators_manual

remain tight. Be sure someone with proper
training and the right tools checks and
tightens the U-bolts on your vehicle. After
the first 500 miles (800 km) of operation,
periodically inspect the suspension 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
life, replace the complete assembly
if cracks or other defects are
detected
• After replacement of any part or
discovery of loose components,
check the torque of all fasteners
• New springs settle-in after the
vehicle's initial service, causing the
U-bolts to become loose
after the first 2,000 miles (3,200 km) of
service and every 60,000 miles (96,000
km) thereafter. Torque recommendations
apply to fasteners supplied and installed by
vehicle manufacture. The values listed at
the back of this chapter (See Suspension
U-Bolts, Grade 8 on page 307 and Frame
Fastener Torque Requirements on page
306), are for cadmium plated or phosphate
and oil fasteners only.
Rear Suspension U-Bolts
U-bolts are difficult 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.
NOTE
To ensure an accurate torque reading,
use properly maintained and calibrated
torque
wrenches. Clean the nut and
bolt. No dirt, grit, or rust should be
present.
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.
NOTE
Whenever possible, torque all frame
fasteners
on the nut end, not the bolt
head.
Load the vehicle to its normal gross weight
before tightening U-bolts. Loading the
vehicle ensures proper adjustment of the
U-bolt and spring assembly
.
MAINTENANCE - Rear Axle and Suspension
Rear Suspension Fasteners
To maintain the performance of the air
suspension, check fastener torque values
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