2004 GMC Sierra Z71 Reg Cab- Rusted out frame less than 100k miles. Mechanic thinks parking outside all these years on gravel the main cause. I don't recall my other GM vehicles over the years with such bad rust problems. I have many thoughts. Perhaps washing the underbody more often and parking on a tarp. Is the steel cheaper these days? Should buy another GM Truck? Did I get my 10yrs of ownshership of money's worth? I am out about tapped out on this truck. Feel a little ignorant if this could have been prevented.