I'll second what DmaxMaverick said with one exception - your tire man might actually be an 'imbicile' rather than an 'idiot'. ![Wink](images/smilies/wink.png)
Most tire mfg's websites have tire load inflation tables that you can download for the reasons he stated.
2003 K3500 Crew Cab, Banks Stinger Pkg, Exhaust Brake & Exhaust, OilGuard Bypass filter, Lube Specialist Secondary Fuel Filter, Allison Deep Pan, TTT Mirrors, B&W Turnover Ball and Companion Hitch, Truck Trunk Sliding Box and V-Box, LINE-X, Co-Pilot Live GPS, Hitchhiker 31.5 LKTG 5th Wheel 28' Wells-Cargo Gooseneck Car Hauler