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6-8 / Chassis
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6-8.2 Frame Fasteners
NOTE: Trucks built after July 2015 use Magni 575 - coated fasteners. Any hardware ordered through
aftermarket will also be Magni 575. Certain sizes of Magni 575 hardware have different torque
values compared to the stander fastener.
Inspect all frame assembly fasteners. Tighten any loose fasteners using the values in Table 6-2 or Table 6-3 for the
proper size/thread pitch of hardware. Torque fasteners using a calibrated torque wrench. Replace frame fasteners
with quality hardware of the same type and grade only.
Table 6-2: Grade 8 Course Thread Fastener Torque Chart
Table 6-3: Grade 8 Fine Thread Fastener Torque Chart
6-8.3 Bumper Extension Carriage Bolts
Torque the 1.00-8 UNC carriage bolts that fasten the bumper extension to the frame assembly to 400 ft-lbs.
6-8.4 Other Fasteners
Standard torque requirements can be found in the Pierce Service Manual, group 9600-P-001, Fastener Identification
& Torque.
Refer to the component manufacturer’s service publications for the proper torque for fasteners installed into
component housings such as axles, engine, transmission, steering gear, and suspensions.
Size
Torque (Standard Coated) Torque (Magni 575)
In-Lbs Ft-Lbs Ft-Lbs
1/4-20 129
5/16-18 265
3/8-16 39
7/16-14 63
1/2-13 96 85
9/16-12 138
5/8-11 191 180
3/4-10 339 285
7/8-9 545
1-8 818
Size
Torque
In-Lbs Ft-Lbs
1/4-28 147
5/16-24 294
3/8-24 44
7/16-20 70
1/2-20 108
9/16-18 154
5/8-18 216
3/4-16 378
7/8-14 602
1-12 895
1-14 918
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