Focus Fanatics - View Single Post - 2012 Titanium Front Strut Low Speed Noise (Clunk/Rattle)
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Old 11-03-2012, 10:27 AM   #1484
Shade-010
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Join Date: Jul 2011
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Location: Noblesville, IN
What I Drive: 2012 Ford Focus SE Sport - 5 Speed

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Quote:
Originally Posted by Zillon View Post
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.
cool beans, man let us know , I don't know why thye would go with such a small bolt for a critical area
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