When I installed my ARB I used grade 8 Equivalent metric bolts and installed an extra bolt through the ARB and frame to keep it from shifting. I accidentally struck a 5" tree last fall and caused no damage to the truck....The ARB had some paint scraped of it. Also a lot of people don't cut down and reinstall the brace that is removed when you install the ARB. IT helps provide a good cross support for the ARB and frame.