Author Topic: Lug Nut Torque Values  (Read 628 times)

Corey Bowcutt

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Lug Nut Torque Values
« on: April 15, 2019, 12:29:15 PM »
Yesterday I did a web search looking for the correct torque to use for my lug nuts.  I found a lot of answers and wondering what is most correct.  My search seamed to indicate the aluminum 10 spokes would get a different value than the steel wheels.  It seems the torque value should be between 80 and 100 ft lbs.  Is there a consensus out there as to what torque value to use for the aluminum 10 spoke and the stock steel wheels?

Corey

JD

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Re: Lug Nut Torque Values
« Reply #1 on: April 15, 2019, 12:59:33 PM »
I've always used 85 ft/lb with a torque wrench in the proper sequence and then go back and check them after a few (25 -50) miles, never had a problem.
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Bob Gaines

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Re: Lug Nut Torque Values
« Reply #2 on: April 15, 2019, 02:11:58 PM »
I've always used 85 ft/lb with a torque wrench in the proper sequence and then go back and check them after a few (25 -50) miles, never had a problem.
+1 . Typical to tighten track driven cars wheels at 100.
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6s1640

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Re: Lug Nut Torque Values
« Reply #3 on: April 15, 2019, 02:33:52 PM »
I've always used 85 ft/lb with a torque wrench in the proper sequence and then go back and check them after a few (25 -50) miles, never had a problem.

What is crazy about that value, imagine back in the day trying get a wheel off with the stock lug wrench.  I expect the 10 spoke lug wrench would bend before breaking the lug nuts lose.  I carry a none OEM tool with extension.

Cory

Bigfoot

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Re: Lug Nut Torque Values
« Reply #4 on: April 15, 2019, 08:18:06 PM »
^^
I think one would want a “breaker bar.”
Even an archaic one would prolly work.... or grab a bigger hammer.
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1967 eight barrel

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Re: Lug Nut Torque Values
« Reply #5 on: April 15, 2019, 08:54:25 PM »
I torque mine to 80LBS in a cross pattern. I know that some of my other vehicles actually had warnings about over-torquing and warping the rotors or stressing studs.
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pbf777

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Re: Lug Nut Torque Values
« Reply #6 on: April 16, 2019, 02:40:08 PM »
     Note that the recommended torque specification per the O.E.M. not only takes into consideration the fastener, but also the effect of the clamping load on the components involved. 

     One example would be the O.E.M. steel wheel, as it does not set flat against the flange it contacts, rather the multi-faceted shaped wheel center creates specific load points, and provides a certain flexibility which aids in reducing localized loading and fatigue. Over torquing may distort this flange defeating this function and lead to premature failure of the wheel, but at least no one will fault one for not tighten the lug nuts, as the nuts didn't come loose as the wheel rim w/ tire fly off! It would seem, particularly with O.E.M. wheels one should follow the factory recommendations (for ones' specific application, not just: "I always tighten them to X") unless one proves something else is truly appropriate due to perhaps the not typical intended environment. Other distortion concerns are present with aluminum wheels (billet, cast or stampings) as perhaps the torque capacities of the fastener may surpass the compressive resistance of the material involved.

     So, keep in mind, if in doubt, or since it's for racing, the statement: "I always tighten the crap out of them so they don't come loose", might not be the best practice.   ;)

     Scott.

greekz

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Re: Lug Nut Torque Values
« Reply #7 on: April 16, 2019, 08:38:44 PM »
I use 75 lbs. on my '66 Ten spokes and '67 Magstars.  Always tight when I check after driving.
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1967 eight barrel

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Re: Lug Nut Torque Values
« Reply #8 on: April 17, 2019, 12:10:31 AM »
Because you can, doesn't mean you should. Aluminum is inherently brittle anyway. 80LBS is plenty. If you change your studs to race studs, then you can use their specifications. As I said, you can warp brake rotors with over-torquing fasteners, not to mention stress and break them.
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shelbydoug

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Re: Lug Nut Torque Values
« Reply #9 on: April 17, 2019, 08:08:26 AM »
80 is a lot. Many times with aluminum, you need to use a spec of "make it tight" rather then scientifically putting a number on it.

IF I put a number on this, I'd say 70 to 75 but put a caution on this. That is with a lubricated thread AND WITH anti-seize compound on the threads.

In MY case, I have not had issues with lug nuts lossening on my ten spokes. That's with 40 years of experience with them.

I will say that IF there is ANY kind of caution here, the stock studs are very short considering how long of a stud the Shelby lug nuts can accommodate. You can easily snap one off with too much torque. DO NOT USE A PNEUMATIC GUN ON THEM.

What I did was go to long ARP race studs that give very close to 100% thread engagement BUT having said that, my 68 GT350 has many changes that would enhance the strength and reliability that was used on many of the Trans Am race cars of the era.

So my reply is full of qualifications. Just make the lugs tight with a standard hand held lug wrench. That puts you right where the torque numbers the engineers measurements came from.

Certainly if you use ANY kind of a wheel spacer, you have qualified yourself as your studs being too short for safe use.  ;)

gt350shelb

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Re: Lug Nut Torque Values
« Reply #10 on: April 17, 2019, 12:01:23 PM »
90-100ft lbs  has been my  number for 30 years  never broke a stud  and alum wheels need  to be rechecked after a  spirited drive ! get wheels hot  and check them.
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