78 blazer rearend not the same..

[Firebirdjones]

I assume at least somebody here already knew that. Boy I sure didn't.

I scored a nice front and rear diff out of a 78 blazer with positraction and 3.73 gears, all new drums, rotors, pads and shoes, wheels cylinders, calipers, all new ball joints and tie rods, center link, brake hoses, wheel bearings,,,,you get the idea. They are brand new inside and out.

I get ready to install the rearend first and found out the shock mounts are staggered. No big deal, I'll just flip one and reweld it....

Not that easy. Not only does my 72 have the rear shocks mounted in front of the housing, but they are further inboard too. So I had to cut and move both shock mounts. It gets better....

I did some more measuring and found out the spring perches are moved outward about 1 1/2" on the 78 rearend. Overall the rearends are the same width but evidently GM decided they wanted more stability and moved the springs outboard slightly.

Sooo, after more cutting and rewelding I have the spring perches where they need to be. I spent all day on that so I didn't get a chance to drop the rearend in the truck. Maybe tomorrow.

Oddly enough, I measured everything on the front diff and it all appears to be identical to the original, springs are in the same places, same shock mounts etc....but I'll probably install the front diff at a later date when I have more time for a front end alignment.

Just thought I'd share.