went through about 4 4.10 rearends( 3 welded 1 open) and 2 4.37 rearends (both welded) peeled a rear housing.. twisted splines on 2 shafts.. LOTTSS of broken ujoints and 2 yokes. never sheered any driveline bolts though.. the housings leave alot to be desired ( they like to peel at the perch which then peels the rest of the housing.. gets ugly) pretty much the only thing that they have going for them is the axle shafts are a hair stouter than a FF dana60 30spline shaft and good ground clearence..