Other Torque Specifications
SAE Grade 8 Steel Set Screws Wheel Bolts and Lug Nuts
Thread
Size Thread Size
Recommended Torque
Square Head Hex Socket
1/4 – 20 UNC 140 + 20 in–lb 73 + 12 in–lb
5/16 – 18 UNC 215 + 35 in–lb 145 + 20 in–lb
3/8 – 16 UNC 35 + 10 ft–lb 18 + 3 ft–lb
1/2 – 13 UNC 75 + 15 ft–lb 50 + 10 ft–lb
Thread Size
Recommended Torque**
7/16 – 20 UNF
Grade 5
65 + 10 ft–lb 88 + 14 N–m
1/2 – 20 UNF
Grade 5
80 + 10 ft–lb 108 + 14 N–m
M12 X 1.25
Class 8.8
80 + 10 ft–lb 108 + 14 N–m
M12 X 1.5
Class 8.8
80 + 10 ft–lb 108 + 14 N–m
** For steel wheels and non–lubricated fasteners.
Thread Cutting Screws
Thread Cutting Screws
(Zinc Plated Steel)
(Zinc Plated Steel)
Type 1, Type 23 or Type F
Thread Size Baseline Torque*
No. 6 – 32 UNC 20 + 5 in–lb
No. 8 – 32 UNC 30 + 5 in–lb
No. 10 – 24 UNC 38 + 7 in–lb
1/4 – 20 UNC 85 + 15 in–lb
5/16 – 18 UNC 110 + 20 in–lb
3/8 – 16 UNC 200 + 100 in–lb
Thread
Size
Size
Threads per Inch
Baseline
Torque* Baseline Torque*
Type A Type B
No. 6 18 20 20 + 5 in–lb
No. 8 15 18 30 + 5 in–lb
No. 10 12 16 38 + 7 in–lb
No. 12 11 14 85 + 15 in–lb
* Hole size, material strength, material thickness & finish
must be considered when determining specific torque
values. All torque values are based on non–lubricated
fasteners.
Conversion Factors
in–lb X 11.2985 = N–cm N–cm X 0.08851 = in–lb
ft–lb X 1.3558 = N–m N–m X 0.7376 = ft–lb
Product Records and Maintenance
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ProCore 648