Peterbilt 579 - Rear Suspension Fasteners

REAR AXLE AND SUSPENSION
5
Rear Suspension Fasteners
To maintain the performance of the
air suspension, check fastener torque
values after the rst 2,000 miles (3,218
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
in the tables below, are for cadmium
plated or phosphate and oil fasteners
only.
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.
U-Bolt Torque
NOTE
To ensure an accurate torque read
-
ing, use properly maintained and cal-
ibrated torque wrenches.
Clean the nut and bolt. No dirt, grit, or
rust should be present.
WARNING!
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.
Rear Suspension Fasteners (Metric and
Standard)
SIZE/TYPE TORQUE
*
Nm Lb-Ft
M16
nylon-insert
nuts
163-217 120-160
M20
nylon-insert
nuts
352-460 260-340
M20 all-metal
lock nuts
427-475 315-350
1/2 in.
nut
109-122 80-90
3/4 in.
nut
394-462 290-340
1-1/4 in.
nut
1,877-2,217 1,380-1,630
* Torque
requirements apply to manufacturer
proprietary suspensions. All other
suspensions must refer and adhere to
original manufacturers shop manual.
NOTE
Whenever possible, torque all fasten-
ers on the nut end, not the bolt head.
5-126 Y53-6047–2C (04/13)