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Old 11-03-2012, 10:33 AM   #1482
Zillon
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No, the OEM bolts are 10.9 bolts.

What seems to be the case, is that the torque spec on the strut mount hardware is hyper-critical. A M8x1.25 grade 10.9 bolt has a torque rating of only 22-27 ft-lbs. That is why these are one-time use fasteners - they are designed to be torqued once and only once to 25 ft-lbs. If they are over-torqued, they stretch, which might induce clunking.

If anything, Ford should have gone with a bigger bolt. A M10 grade 10.9 bolt has a much higher torque rating at 45-53 ft-lbs.

Alas, I have no scientific proof just yet. I'll know more later today.
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