72 lesabre 8.5 28 or 30 spline?

im pretty sure its a 28 spline but wanted to make sure since they arent the same as a skylark but is it a 30 spline or 28?

 

Are you sure it's an 8.5 rear? I didn't think they put those in the big cars in that era.

 

28. Small block cars got the 8.2/8.5

 

The 30 spline 8.5s didn't start until 88 or 89. 72 is a 28 spline for sure.

 

ty all. i had bought a posi for my 66 (has a 72 rear) so i can use it on this since this car is up and running. now just curious but are the big cars axle any wider than say a 73 regal? they dont look it.

 

Big car rears in the 1971 - 1976 era are the widest car rear ends. 64" to 65" drum to drum

 

whats that vs a 73-77 regal. apparently a guy put a 96 impala ss or 9c1 caprice rear in a 74 lesabre on a facebook group the other day and it was a direct swap. i know the later 77 up b bodies share rears with a 73-77 a bodies but no clue on the earlier ones. i have found out the sway bar is the same on a 71 big car as a later a body.

 

roadmasters and none performance caprices are 61.5 , 63 for the ss and the wagon is 64.5 wide according the ss website. so im guessing the modern wagon is the same width as a 71-76 b.

 

I came up with 63 so apparently the 8.5 cars use the same width a later b body and a body it seems. Not sure about other rear in big blocks. Im guessing they are wider and same as later wagons. Now if i could find out if anything shares front end parts.

 

1971 sway bar will not fit on any era but the 1971 - 1976 BIG CAR - these are the widest rears gm ever produced.
1973 - 1977 A-body and 1977 -1996 B can interchange rear sway bars as the lower contril arm width is the same center to center. NOW the sway bars may have different kind of mounting hardware... but all should mount on the bottom of the control are with a U channel support with bolt usuall 4 on each lower arm for the 1973-1977 and the later in the 90 -96 were slightly different with bolts going vertical through the top of the control arm sometimes... Either way you can make them work.
Jim
JD Race

 

thats what i have is a later 73 up or 71 big car sway bar. not sure they had rigged it up on a 71 skylark by bolting angle brackets to hold them. idk if that worked well but it was on there. it fits the car. i was told it was from a 73 regal. idk if the 8.5 vs the other 9 and something rear end is different widths but my rear is exactly the same width as a 96 impala ss or 9c1. i measured it 3 times to be sure lol. i also found that online people had put 9c1 rears under 74 b bodies a delta 88 was the one i read about.

https://www.impalaforums.com/threads/rear-end-swap-on-a-72-impala-from-a-96-impala-ss.1860823/ just for example.

 

1973 - 1977 A-body is the same width as 1978-1996 sedan B body. ...BUT NOT the WAGONS.
Which I already stated once before.
The sway bar from a 1971 - 1976 FULL size B C body is WIDER than a 1978 -1996 B Body totally different width sway bar... they may look the same... BUT if you lay them on top of each other you will see 1971 - 1976 B C Full size car sway bars are wider .... Just wider lower control arm center line. They will bolt onto the lower control arm the same way on the bottom.
1964-1972 A body mount inside the inner side of the rear control arms .
Jim

 

it fit idk?