shogun32
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Sorry to necro-thread but nobody posted any actual engineering! A wheel is held in place by friction between the clamped surfaces. If the wheel stud or the 'nose' of a hubcentric spacer is taking sheer loads you're a goner. It means your friction limit has been overcome and you didn't have the parts clean but definitely not clamped tight enough.
https://www.fastenal.com/content/feds/pdf/Torque-Tension Chart for Metric Fasteners.pdf
The reason for the difference between <2015 cars and after is the fastener size and thread pitch. The yield on the threadforms are different. Basically you want 75%+ of yield strength. That's why everyone's lookup table spits out basically the same value.
In practical terms you want absolutely no less than 9,000lbs (85ft/lb) of clamping force (unless you have data otherwise) or alternatively 65% of yield on a bare AL wheel. 12-14K (110-130ft/lb) is a MUCH better place to start. If you have spacers especially ones with slick surface treatments, you'll want to consider 16K (148ft/lb) your lower bound and maybe shoot for 18K (165ft/lb) not to exceed 19K (175ft/lb) assuming your fastener (M14x1.5) can withstand it. All the above assumes clean threads and an accurate torque wrench and technique.
In any event, RE-CHECK YOUR TORQUE shortly after you initially set it to catch anything amiss. Nuts can loosen from vibration, wheel wasn't seated square, changes in temps, etc. It's not a one and done task.
https://www.fastenal.com/content/feds/pdf/Torque-Tension Chart for Metric Fasteners.pdf
The reason for the difference between <2015 cars and after is the fastener size and thread pitch. The yield on the threadforms are different. Basically you want 75%+ of yield strength. That's why everyone's lookup table spits out basically the same value.
In practical terms you want absolutely no less than 9,000lbs (85ft/lb) of clamping force (unless you have data otherwise) or alternatively 65% of yield on a bare AL wheel. 12-14K (110-130ft/lb) is a MUCH better place to start. If you have spacers especially ones with slick surface treatments, you'll want to consider 16K (148ft/lb) your lower bound and maybe shoot for 18K (165ft/lb) not to exceed 19K (175ft/lb) assuming your fastener (M14x1.5) can withstand it. All the above assumes clean threads and an accurate torque wrench and technique.
In any event, RE-CHECK YOUR TORQUE shortly after you initially set it to catch anything amiss. Nuts can loosen from vibration, wheel wasn't seated square, changes in temps, etc. It's not a one and done task.
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