Peterbilt 579 - Page 341

FRAME
Every 60,000 miles or 6 months:
• Refer to specic manufacturer's
literature for any special
instructions.
• Remove fth wheel from vehicle.
Refer to the Shop Manual, “Fifth
Wheel Removal.”
• Steam clean the fth wheel and
mounting brackets.
• Check all moving parts for
excessive wear or damage.
Replace all worn or broken parts.
• Complete two-month service
procedure.
• Install fth wheel. Refer to
the Shop Manual, “Fifth Wheel
Installation.”
Frame Fastener
Torque
Requirements
Standard Grade 8 UNF or UNC and Metric
Tighten all frame fasteners with a
torque wrench. Torque specications
apply to the following fasteners with
lightly lubricated threads.
NOTE
Whenever possible,
torque all frame
fasteners on the nut end, not the bolt
head.
FASTENER
SIZE
TORQUE *
Nm Lb-Ft
5/16
22-30 16-22
3/8
41-54 30-40
7/16
75-88 55-65
1/2
109-122 80-90
9/16
156-190 115-140
5/8
224-265 165-195
3/4
394-462 290-340
7/8
517-626 380-460
1 952-1,129 700-830
1-1/8
1,346-1,591 990-1,170
1-1/4
1,877-2,217 1,380-1,630
METRIC WITH
NYLON INSERT NUTS
M5 8-12 6-9
M6 9-15 7-11
M8 23-31 17-23
M10 33-43 24-32
M12 75-101
55-75
M16 163-217 120-160
M20 352-460 260-340
* ESNA
Style Lock Nut, with nylon insert.
Lubricate nylon insert nut lightly with SAE
20/30 oil.
5
(04/13) Y53-6047–2C 5-105