Broken wheel stud

[donnreeves]

This kind of goes hand in hand with the post about changing studs with aluminum wheels. I switched to aluminum wheels, but didn't change the studs because there was a couple of treads showing with the nuts tight. I can't understand how an extra 1/4" of thead sticking out is going add strength to the stud. That said, on our last trip I broke a front stud. I did get stuck in a lane with raised manholes, and hit a couple hard. Can someone enlighten me as to why the studs are weakend if not enough treads are showing?What is the difference if two threads are showing or a 1/4" of them? The threads go all the way to the hub, there is no shoulder. Do the longer studs have one?  Donn

[TomC]

When I changed to aluminum wheels, the mechanic kept the front studs as is, which makes them flush with the nuts.  I believe there is some sort of DOT rule with commercial vehicles that require x amount of stud beyond the nut, but it eludes me at the moment.  Since we are not driving commercial vehicles, those rules don't apply.  Also, since I always check my tires and wheels at least every 2 hours when driving, it doesn't bother me.  Good Luck, TomC

[donnreeves]

Update on broken wheel stud. I just removed the broken stud and it puzzles me. It's a very clean break right in the middle of the nut. I would expect a break at the inside edge of the nut or where the stud meets the hub, but not inside the nut. Maybe it's just one of those deals that can't be explained.  Donn

[Len Silva]

Don,
I don't think it makes any difference whether you have three threads showing (the minimum I would want) or a 1/2".  It's not goint to affect the stud strength.  My guess is that sometime in it's life, that stud (and probably all of them) was over tightened and that's what weakened it.  The rough road may have done it in.

FWIW,

Len

[buswarrior]

Hello Don.

Check the other studs very carefully to see if there is any change in their radius along their length.

Also, whether the individual threads are consistantly shaped over the whole length.

A really stretched stud is skinny in the middle somewhere. An overtightened stud will show the threads pulled under where the nut was yanking on them.

If one broke, I'd be a strong supporter of changing them all out, since the rest have been sharing in whatever nastiness has been done to them.

happy coaching!
buswarrior

[lloyd]

As long as the nut has threads sticking out the end it is as strong as if there was 1/2" sticking out. You might have had a stud with damaged threads, it might not hurt to check the rest.
Lloyd

[NJT 5573]

In normal use, wheel hardware gets used up. One missing lug out of ten is not enough to meet the DOT Out of Service Criteria and alot of trucks run with a bad stud. Commercially speaking I don't throw away good studs but I'm sure some people do. I generally know how old my studs are and often find damaged studs after just 1 or 2 wheel changes. I could change all 10 every time that I have 1 or 2 studs torn up, but I just don't want to spend the time or money if the exhisting studs are relatively new and in good condition. In my experience the stripped threads come first and only if the nut siezes does the stud break, most of the time the stud is just left threadless. Judging from where yours broke, I think it was just defective from the beginning. I can do all of my own work and would have replaced the stud and been gone in a few minutes. My mechanics would have knocked the assembly apart and replaced the hub, drum, shoes, seals, and bearings with new parts, just to be safe, because that is their job. Much of the value of a good mechanic is knowing what can and cannot be reused. Most mechanics won't reuse anything because some people can break a hammer. The insights I have shared in my posts are for the do it yourselfers working on their own equiptment with a desire to be quickly back on the road with a satisfactory repair and enough fuel money still in our pockets to safely get home. If you go to a shop you should expect and get a "quality" repair and you can't beat all new stuff!