Service and maintenance
8.4 Checking tightness of fastening bolts
The general tolerance for the tightening torque is 10 %. The tightening torque is based on a
friction coefficient of μ = 0.14.
Table 8- 3
Thread size
M4
M5
M6
M8
M10
M12
M16
M20
M24
M30
M36
38
Tightening torques for fastening bolts
Tightening torque for strength class
8.8
[Nm]
3
6
10
25
50
90
210
450
750
1 500
2 500
10.9
[Nm]
4
9
15
35
70
120
295
580
1 000
2 000
3 600
Operating Instructions, 02/2018, A5E38093971A/RS-AB
12.9
[Nm]
5
10
18
41
85
145
355
690
1 200
2 400
4 200
BA 2012