Don't know if its a direct swap, but I'm sure that rear in your '73 Centurian is stronger than the Chevy 12 bolt if in fact its the 9 3/8ths rear.
It probably depends on what year the Impala rear end is. Will that Impala rear fit into a '73 Impala? If so then if the Centurion is a B-body then the answer is probably yes. As Mark said the 9 3/8" rear is stronger but if you want a different more desirable gear ratio, you will more than likely be SOL trying to find an old factory one because no one reproduces any gear sets for the 9 3/8" in which case the 12 bolt is MORE than adequate. GL Derek
I think if Impala rears fit where 9 3/8 rears were, no one would bother trying to keep the aftermarket abandoned Buick rear. So I say, no.
Well if the frames are interchangeable then the rear should fit. I can't see them making the frames different for the different makes of B-bodies when all the A-body frames are interchangeable. But I can't say for sure so start by confirming that the frames are the same and interchangeable. The difference in the 9 3/8" rears to the 12 bolt that I know of is IIRC the rim bolt patterns are different on the axles so different rims would be required.(9 3/8" IIRC has the 5X5" bolt pattern while the 12B has the 5X4 3/4" bolt pattern) Maybe you haven't heard of this swap so much is because no one wanted to buy different rims? Derek
Some of those cars got a Corporate 8.875 in that era IIRC, I seem to remember seeing that on the JD RACE website, which with this new hard drive I don't have it saved anymore, so? If it does have an 8.5" in there and if a '65 is the same as a '73(I can't remember) I have an 8.2 with 3.36:1 gears you can have, the original out of my '65. I have a 12 bolt in my '65 now with a 3.07/posi. The 3.36 rear isn't posi but for the price you can convert it with the $ you save. It will need something like that because I tried a Lincoln locker with that one and broke stuff. The gears are good but the spider gears not so much. LOL Can't remember if the 12 bolt had brakes on it or I took the backing plates from the 8.2 and bolted them on the 12 bolt? Let me know if you want it. Derek
Thank you so much everybody. Especially Derek for offering a free rear axle! I was bidding on a Centurion with a broken axle, but did not win it. It had a broken axle and there was an Impala rear in the same area. I just wanted to have it road-bound for cheap. Thank you.
stick with the 1971-1976 FULL size Buick Olds Pontiac or Chevy. They will all interchange. I have a 3.73 posi rear that will fit if you need. NOT the prettiest housing but all the guts are NEW and will be great for some big car fun. JIm