I'm on my third ds in my rcsb with mods in sig. The first was at 7000 miles with the 3.42's in it at bout 110 mph. Thought it may be a fluke. Bought a second gm stock draft(new) and right after installed the 4.10's. It came out at 90 mph. And gm was zero help. Said they weren't having any other problems/complaints. I called bulls**t. Ended up having ja main Powertrain in Jackson ms build me one that was 3.5" diameter, thicker walled steel with upgraded 1330 joints on both ends. No problems so far in 3 + years. Btw, factory shafts were steel also.