This isn't really chevy question but I'm sure some of you can help. We just got a replacement dump truck for the cemetery. It's a F350HD (I don't get to choose what trucks we get). I been looking it over and preparing it for our use (installing hitch, cd player, ec...). Our old dump truck was 4wd, this one is only 2wd and I know I'm going to have some traction issues. I believe the rear is a D70 due to the big 70 cast on the top of the diff. I'd like to install a locker in the back. What can you tell me about the strength of this axle? It's a FF axle I can tell. The truck itself weighs 7,200lbs and will routinely haul an additional 6,000lbs of dirt in the cemetery from graves. Will a lock-rite be able to handle that kind of stress, a detroit? I want something I can install myself without having to reset the gears. How about the axle shafts? Thanks in advance.