I have a set of oem low mileage 4.10 front and rear ring and pinions and a set of 4" blocks with u-bolts. The gears are out of a Dana 60 reverse and a 10.25" 12 bolt. They are in excellent shape and quiet.
I switched to 3.55s and 2" blocks.
I switched to 3.55s and 2" blocks.