"supposed to" different from "must do".

If you torque to spec the bolt well break after about 4-5 cycles. It will be noticeably damaged by the third.

However if you pre tension to say 50 N·m and torque to angle 45° vs 90° (I think 65 N·m + 90° is spec), you will achieve something like 80% of the spec clamping force without causing any additional damage to the bolt. (reminder bolt is damaged at the factory on purpose you can not undo torque to yield stretching)

Best to get some 12.9 bolts and torque to spec. Bolts will never wear out and will have similar torque as the 10.9 torque to yield

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)