Are Chevelle 12 bolt axles the same length both sides? Or is one shorter like a 9 inch.

Same legnth.

'65 to '67 Chevelle, El Camino, '67 to '69 Camaro and '68 to '70 Nova 29 5/8 inches. '68 to '72 Chevelle, El Camino, '70 to '72 Monte Carlo and '70 Camaro 30 1/8 inches. Both sides are the same.

Okay, something is very weird here. I was just out in the garage with a tape measure. I picked up a 12 bolt date coded for 1969, its a Chevelle rear has the ears on top overall length from wheel flange to wheel flange is 61 inches. It has a spool and strange axles with c clip eliminators. The axles are different lengths left is 30.50" from wheel flange to inner end, right is 29.50". This rear had a bunch of brackets welded to it to make it fit in an unknown car at some point in its life. I was curious if anyone had altered the housing besides all the brackets, So I started measuring the 10 bolt housing that is in my Camino, overall aprox 61 inches [hard to measure all assembled in the car on the ground] the left axle tube measured from the end of the center casting to the back of the flange that the backing plate bolts to is 18.25" the right is the same, the center casting is 17.00" all this totals 53.50" now I go over and measure the 12 bolt the same way left tube is 17.75" right is 18.75" center casting is 17.00" all total 53.50". My questions are, did someone change the length? Are 10 and 12 bolt housings that different dimentionally? Can someone measure there 12 bolt for me so I can compare? Why are my axles different lengths? why are my axle tubes different lenghts? Is this normal because 12 bolt rears have a different pinion offset? WTF :confused: Help! Sorry for the rant, I took an oxy about 1 hour ago for back pain, this all could be a dream,:boring: I don't know, those things make me loopy.

All Chevy car rear ends have the pinion offset 1/2 inch to the right. This makes the pinion 1 inch closer to the right end than the left. The axles are the same length. Your axles are not right. I don't know if it has something to do with the spool that is in it, or if someone ordered them wrong. It doesn't matter if it's a 10 bolt or 12 bolt, the housing measurements are the same.