12 Bolt vs 10 Bolt Rear

[Chipper Chapman]

The statement made that the pinions are different is right, I stand corrected. The pinion shaft and bearings are actually larger in the 8.5 than the 12 bolt. Maybe gm new what they were doing when they replaced the 12 bolt with the 8.5 and placed it under millions of cars and trucks lol. Once you put spool and axles in it, they won’t know they’re not in a 12 bolt housing. Run it!