Don't use AZ on lug nuts? Not so sure about that. My Porsche owners manual says to use "anti seize paste" on the threads and washers but not on the cones that contact the wheel. Porsche is very conservative in all their requirements to ward off liability and lawyers. Good enuff for me.
Interesting. They think it's the cone of the lug nut and it's contact with the wheel that set the torque. I never thought of it that way
Or the stud has issues!There's a few things going on when lug nuts are hard to remove.
- lug nuts could be 19 mm and not 3/4" for example (wrong socket)
- socket is at an angle/not fully on the nut (poor practice)
- ss caps on lug nuts have been beaten up and distorted by impact wrenches, especially during removal (poor practice)
- overtightening and/or stretching (poor practice)
- improper lighting (energy conservation gone wrong)
- not using a light lubricant on the threads to counter corrosion (Fluid Film deficiency)
The issue is usually the nut doing the wrenching. Wrong socket, wrong angle, wrong grip, all wrong. Doesn't take much to bugger up a nut or bolt head.Or the stud has issues!
When I use antiseize on bolts, I use 20% less specified torque. No issues in several decades of wrenching.Lug nuts should never be lubed because it interferes with torqueing the nuts properly. When lug nuts work loose it is almost always because of lube on the threads.
When I was in university for engineering, one of the final exam questions was "Explain from first principles why threads should never be lubricated when torqueing". The answer required calculations of force, friction, and yield strength. One of 4 questions in a 3 hour exam so the expected answer was far more than a paragraph or two.Every car manufacturer warns you against using any kind of lubricant on the stud threads.
You're just lucky, that's all.When I use antiseize on bolts, I use 20% less specified torque. No issues in several decades of wrenching.
For the lug nut bolts, I've been using one of the old mechanic's tricks One drop of used motor oil in the middle of the threads. Supposedly this is just enough to prevent galling/rusting, but not enough to affect dry torque specs.
The only times I've ever had an issue with lug nuts loosening on me was when I had a shop do something for me.
Warnings are usually in a "Warning Box". I can't find the Chapter and Verse in my Owners Manual that contains that box.Every car manufacturer warns you against using any kind of lubricant on the stud threads.
Something to think about:Before installing the nuts, place 2-3 drops of motor oil on the clean threads of the studs and 1-2 drops of motor oil between the washer and the nut on the two-piece flange nut. This process reduces friction and allows you to achieve a desirable clamping force once the wheel is torqued down.
We don't use the "star" pattern for no reason. It helps with consistency and is one of the reasons I torque up in stages.In a nutshell, torquing a dry bolt has two issues. One, on an overall basis you produce less clamping force by torquing a dry bolt. Two, and much more important, is that the clamping force variation from bolt to bolt is far higher with dry bolts than it is with lubed bolts. That is intuitive when you think about it. The variation bolt to bolt produces leaks and warpage in the parts you are joining.