When I junked my '77 GMC cab,that was empty,no seats,dash pad,etc,it weighed in at 420 lbs...the fleetside bed I scrapped I dont know for sure exactly how much it weighed because I loaded it full of scrap before I hauled it in,but my truck weighed 400 lbs more with the flat bed I made for it after installing it (flatbed was 900 lbs all by itself!),so I would guess the fleetside bed probably weighed 500 lbs maybe,mine had a lot of rot and missing metal,so I'd add 100 lbs for that..................................................................................................