Or did the previous owner of my particular one maybe do a downgrade to make a few bucks before he sold it? Today I was looking at an old book about TBs, and on the list of Buick rear end codes it didn't give a code for an 8.50 rear in 1987, only 7.50 and 7.625. The 8.50 was listed for every year before that though. My rear apparently no longer has the sticker with the codes, but on a G-body forum I read that you can measure the distance between the bottom bolt on the cover and the bolt either to the left or the right of it. On a 7.5 rear the distance will be 3.25", and on an 8.5 rear the distance will be 3.75". Sure enough, I measured mine and it was 3.25". The corners look like the pics I've seen of 8.5 rears, however. Anybody have any idea if the 3.25" vs 3.75" thing is B.S.? Or could I actually have a 7.5 rear?
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