Oohkay… I will tomorrow morning tourque my steelies. Must have made a mistake a few years ago when I researched the tourque for my wheels like „oh 150, fine“ without thinking about someone was writing about ft-lbs.I tend to agree with this. Torque spec for steelies is 154ft-lbs, so the studs should be able to take way past the 97ft-lbs spec for alloys.
So my car is driving since years with 150Nm‘s -> 110ft-lbs…. and I did alot of sketchy stuff with the car (you wouldn’t believe how far a 200 can jump…).
Maybe the good thing is that I had removed the tires like every half year to work on things at the car. Maybe this and the fact that steelies are a bit more tolerant saved me from a situation like it happened to OP.
And yeah I also think that they might got kina loose over time or didn’t had enough tourque -> that damaged the studs with the years/ months/ whatever -> then the retightening with the right tourque finaly killed them.