Broken Wheel Studs

[Number_35]

When cycling or on foot, I often stop to pick up nuts, bolts, and washers.

This morning I found these two only a few hundred metres apart, but fortunately it looks like they're off different cars.

The shorter one at the bottom has part of the sheared-off stud inside.

I wonder if the top one is an intact stud off a European car.

 

[eljefino]

Bottom one is off a Toyota alloy wheel.

 

[Barkleymut]

Just curious, is this on a long flat area or is this on dead mans curve?

 

[Number_35]

Just curious, is this on a long flat area or is this on dead mans curve?

This is a flat straight road with a 60 km/h speed limit. One was near an intersection. I never thought about it before, but wonder if braking can stress marginal studs.

 

[Jetronic]

I would expect temperature changes to be the bigger issue, the metal clamped by the stud and nut expands when hot (aluminum more than steel) and if the sud doesn't expand the same, the stress increases, eventually fatigueing and breaking the stud. Overtightening doesn't help.

 

[Klutch9]

Bottom one is off a Toyota alloy wheel.

Some Kias use this style as well. Our Carnival does. Was news to me when I saw it, as I also thought it was just a Toyota thing.

 

[KrisZ]

That is why I always double check the lugs with my torque wrench after someone else ale works on them.