I've replaced lug studs on 240's easily, hopefully the same on a 740. They're only a few bucks each. When replacing the rotor is the ideal time to do it. On a 240 just use a large hammer to knock it out. Then tightening down when putting on the wheel brings the serrated edges in, you will have to tighten a bit until snug, and you see it's the same distance as the others. FCPGroton has lug bolts and nuts.