Yes, the 14 bolt is a GM corporate axle- - -a very good one, BTW, somewhat heavier-duty than a Dana 60. The dual-wheel 8-lug Dana is actually a Type 70, not a 60. The type 60 is intended to be a heavy-duty 1//2 ton rear end, or a 3/4 ton when it has 8 lug wheels and full-floater bearings. It's possible to install longer lug studs in type 60 hubs and run dual wheels, but the brakes are a bit too light-duty, and the wheel back spacing isn't exactly right for an average 1-ton chassis.
Jerry
