Gents, I got this thing to use in a '57 Chevy panel truck that I'm building here: http://www.jalopyjournal.com/forum/showthread.php?t=805553 I was told it was a 71 Firebird rear over the phone but found out it was an early Camaro 8.2 when I went to pick it up. Ok, no big deal. The seller had paperwork to prove that it had been serviced at a rear-end shop and everything looked good. It even had complete brakes etc. I get the thing home, lop off the spring pads and throw it under the panel with new pads. I quickly "centered" it by pulling a dimension from outside of frame to backing plate on each side. I didn't weld the new pads for lack of time. Today I pull the same dimensions from frame to backing plate & nothing has changed. The next dimension I pulled was from frame to pinion center...It was off by almost an 1"...! I drive myself crazy taking every dimension to verify that the frame isn't bent and that the body is on the frame straight etc. etc. until I measure backing plate to pinion center on each side. The pinion isn't centered! I assumed on a Camaro it would be. Has this thing been modified? What is it from? Now I'm just curious because I'm not planning on using it. The code looks like SP 0210G2 and doesn't show up in standard searches. Any help is appreciated.
It shouldn't hurt a thing if the pinion isn't perfectly centered as long as your engine/trans and rearend are mounted square in the frame. It is already offset vertically. It won't hurt to be offset horizontally. the driveshaft doesn't know the difference. According to the casting number it is a Chevy 10-bolt. I did a search for the stamped numbers too and couldn't find anything. Maybe take some sandpaper to the axle tube and make sure of the numbers. What is the width from wheel mounting surface to wheel mounting surface?
Thanks for the reply. Width is 60". I did some more measuring & it is out of center by 5/8". You're saying the u-joint can handle it? That'd be welcome news...
off center is normal. take a picture of the rearend from the back, so we can see what it looks like. the casting numbers are not very helpful.
Absolutely! At 60" wide it a couple of inches narrower than the original axle in your truck. At 62.5" the 1970-81 rear might actually be a little closer fit.
Yeah, original is 62" which is why I originally was looking for a 70-81. Anyway, 60" will work and I have wheels with a backspace to get the wheel centered in the wheel well. Happy to hear that the pinion thing is not a problem. I've set a few rear axles in cars/trucks before but they have all had a centered pinion...Learn something new every day. Thanks, guys.
The offset (horizontal) pinion angle has to be included with any vertical pinion angle, as they now become a compound U-joint angle. Finding the actual angle requires careful measuring, and some math, to keep within the normal operating limits of a standard single cardon U-joint, normally 3 degrees. You might want to spend some time looking at the link below to learn more about this subject. http://www2.dana.com/pdf/J3311-1-DSSP.pdf
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