<VV> Anti-seize on wheel nuts

[J Bruce Weeks]

<Do you live in the rusty east? I do and I use anti-seize, grease, oil, 
whatever is handy. I have swapped thoudsands of wheels and the only one .that came off was the one I NEVER tightened.

<Of course, anti-seize does change the torque values needed to clamp the wheel correctly. One can use anti-seize incorrectly and that's when the lawyers get involved.

<I only worked on cars, not large trucks. I see research was done for the 
large truck industry, including Budd or stud centered wheels, and dual 
wheels. (A direct result of the NHSRA investigation) These wheels NEED oil on their threads for the torque values to be correct. (The change in bolt tension is astounding between dry, lightly oiled and over-oiled- in the 50% range)

<Anti-seize, while changing the torque required by the same percentage as on any fastener, since the value on truck wheels is solarge, the difference is enough to cause overtorquing if values are not adjusted. And the results can be what you predicted, including lawyers again, after a loose wheel causes mayhem. I see your point on large truck wheels. Did your research find wheel offs from cars in the 100 ft-lb or less torque value category? (Same results as large truck wheels except over-oiling can increase the tension in the bolt and collapse the wheel bosses. This will allow the nut to loosen as the boss provides spring tension to maintain bolt tension.)

Only 0.2% of truck wheel end disturbances (any reason a wheel is removed and replaced) at the time resulted in a wheel-off. 98% of those wheel-offs occurred within 600 miles. 

Truck wheel nuts need a retorque at about 125-150 miles. Trucking companies would not perform a retorque until their first stop at the next terminal. Guess how far the average distance between terminals is? 700+ miles!

So if any particular wheel was going to come off, there's a 98% chance it's already gone before the next terminal.

Ultimately, NHSTA ruled that the design was adequate when maintained properly. However the manufacturers had differing recommendations regarding stud oiling and retorque intervals. So we were directed to consolidate the recommendations into an industry standard. This was done through the Truck and Bus Council.

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