[DougD]

If I was going to the trouble to replace the fasteners in my suspension (and I'm not), I'd use AN and nothing else. If you plan to use hardware store fasteners in a suspension application, you're taking more of a chance than I'd be comfortable with. I'd suggest reading one or more of Carroll Smith's race car preparation books (Prepare to Win, Engineer to Win) as to why and where. In suspension applications, grade 5 and grade 8 may not cut it when you factor in the physics they're exposed to. Even the basic design of these fasteners precludes their use in some instances, i.e., bolts that are threaded for their entire length, etc.