Frame And Members problems of the 2007 Chevrolet Colorado

I own a 2007 chevy Colorado. I am very careful when it comes to my vehicles maintenance and take all precautions. When it comes down to a simple routine such as tire rotation, as many americans with the know how do, I performed this myself. With a four way and a torsion bar set at the factory 100 lb setting. Before I even used the torsion bar, the wheel stud had broken with no more than 30lbs of pressure. I took my vehicle to a local gm dealer and was told it is not covered under my warranty. I argued that regardless of who had worked on it, the stud still would have broke. So now I am driving around with a missing stud and I am concerned about the safety of my vehicle. I believe that this is a poorly produced part and should be replaced by my factory warranty.