Breaking front wheel studs

kbierersr@gmail.comI drive a 2006 kenworth T800 tri axle dump, I have been having front wheel studs breaking on a regular basis, I'm talking alot sometimes four or five a day, other times less. It's happening on both sides. I have aluminum bud wheels with the big floater tires. My loads are 22 to 26 tons Road conditions are bad, but none of my buddy's are having any problems like I am. The lug nuts are torqed at 500, factory numbers, I have inspected the king pins, wheel bearings, for bent wheels, checked the center hole in wheel for wear, none found. The studs break in different locations,sometimes flush with the wheel, or deep in the wheel and sometimes some stud is still sticking out of wheel. And as you know the studs them selves don't take any weight, the weight is taken on the center section of the wheel, the studs just clamp the whell to the hub. I am at a lose why all these studs are breaking, Please help!