<VV> LH lug nuts

[Joel McGregor]

If all the surfaces are clean and the nuts are properly torqued the wheels don't fall off.  The problem is they often aren't clean and thus you have wheels fall off.
If a stud is stretched it should be replaced.  As you said they are like springs and once they are stretched beyond their design they no longer have the proper strength.
Torque has to specify dry or lubed threads to have any meaning because the values are so different.
If torque needs to be really precise it will be listed in bolt stretch.  Common practice on rod bolts.

-----Original Message-----
From: VirtualVairs On Behalf Of Hugo Miller via VirtualVairs
Sent: Monday, March 23, 2020 7:11 PM
To: virtualvairs at corvair.org
Subject: Re: <VV> LH lug nuts

I take your point about 'bolt stretch', but if all the faces are clean it is irrelevant. Only if you have enough dirt, rust or paint on the faces, and that subesquently wears off (as it will) with the expansion & contraction with the temperature changes, together with all the other forces at work - only then does it become an issue.
I rebuilt a Kenworth W900 a few years ago, and the rear wheel fixings were exactly the same as my buses back in England, with the exception that there was no wheel spacer fitted. The idea of the spacer, incidentally, was that you would remove the spacer if you fitted thicker Alcoa wheels - saves changing all the wheel studs.
The trouble with using a torque wrench is that most people fit the lug nuts dry. If you try t fit a dry lug nut onto a stud that has been stretched by previous over-tightening, much of the applied torque will be taken up in turning the nut on the threads, rather than stretching the stud. And that is an important point also - studs and bolts act as a very strong spring, clamping everything together. The old British Triumph motorcycles never gave a torque setting for their big-end nuts (con-rod bolts, that is). They specified that the bolts be tightened until they stretched 1/8". (It may not have been 1/8", but that is the principle).
I reckon I can tell by feel whether a nut is stiff on the thread or whether it is stretching the bolt. A torque wrench, on the other hand, can't tell the difference. I have occasionally checked my wheel nuts with a torque wrench, just for curisity, and I can get them as near spot on as makes no difference (about 450 lb/ft is the spec). And my wheel nuts never come loose. And even if they did, it wouldn't matter, as four nuts on each wheel are secured by retaining clips.