Keep Your Studs Clean!: If you don’t, you could lose a wheel!

I ran across this tech article on a BMW enthusiast website. Good article, until I saw this picture: 

 

 

 

If you apply any friction modifying substance, like oil or anti-seize, to the wheel stud threads, it is going to change the measured torque values. With less friction on the threads, the torque values increase. So, when you tighten a wheel to 85 ft/lbs, it may actually be torqued at 95 ft/lbs (this includes torque wrenches and sticks). The increase in force will mean that the studs will stretch under the increased torque. This stretching can lead to metal fatigue, changes in thread geometry and the possible failure.
If you encounter a vehicle with anti-seize on the wheel studs, be very careful. Take time to explain to the driver why anti-seize is bad and how it can cause problems. Also, advise them that there is a potential for failure during normal service. You should also put it on the repair order.
Is there a right way to use lubricants around the wheel? Yes, but it has to be a high-temperature lubricant used only in a very light coating. First, a high-temperature lubricant can be used where the hub goes through the center of the wheel. Many vehicles use the hub to center the wheel. These “hub-centric” designs can benefit from a very light coating.
On some conical lug nuts, you can put a light coating on the seating surfaces of the cone, while avoiding any contamination with the threads. This coating can prevent corrosion. Thank you Ed, for setting me straight.
But, in a 1994 Ford TSB they did say it was alright to use anti-seize on studs for some F-250 and 350 trucks, these studs and lugs are so stout and strong, a few extra or less pounds of torque are of little consequence.

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