Does anyone know the dimension of the U-bolts for the 8-1/4 Rear End?

 

I want to say ~2.5" or 2.75" but may be wrong.

 

is that width wise?
would the lengths and diameter be the same?

 

I think they are 1/2" diameter and 2.5" wide. length can be anything as long as teh thread go far enough down, then you can just cut off the rest after you install them and torque them down.

 

all 8.25 rears use 3" u-bolts across the board. A little extra info about the 8.25... they only came with either the 7260 or 7290 style u-joints, all are large bolt pattern, all of the axles are 27 spline prior to 1997 then they were 29 spline. There's an oddball 8.25 out there that has a 2.45:1 gear in it, the case is "special" and you can't put any other gear in it. You are more than likely to find this gem in 78-79 M bodies. The 8.25 hit the scene late 68 early 69 in low powered B-bodies. The police car versions had 11 inch drums on them. The gear ratios from the factory ranged from 2.26:1 to 3.91:1. The 3.23 is a rare find if you find one.