Technical 1949 Oldsmobile differential interchange

I have a 1949 oldsmobile 76 model . 350 chevy , turbo 350 , stock rear . I think it is a 3:64 ratio.. what rear center sections would interchange / direct swap . I would like lower gears 3:00 or 3:23 .... also what late model rear would fit? thanks andy

 

I think Olds and Pontiac 3rd members will fit through 1956. There were some 3.23's in 55 and 56 Olds, mostly in the 98 models.

 

I would gear center section swap if possible. Lots of bracket cutting rewelding on the 41-50 rear housing, if you swap to a later rear complete housing

here is a big thread on Olds/Pontiac rears. Maybe the center will swap up to 1956? If the splines match for the spiders. 3:23 is common mid 50s

http://www.jalopyjournal.com/forum/threads/pontiac-olds-rearend-tech-post-it-here.129676/

There was a 3:08 in the cl***ifieds


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Don't know about the third member, but I put a set of 4.30's (ring & pinion) from a '39 in a '50. By the way, 3.0 or 3.23 are higher gears.

 

does anyone have a hollander interchange manual .. if you do can you look up which center sections are interchangable with a 49 olds ... also the 3:08 i saw in the cl***ifieds was for 57-64 .. if there is an earlier one let me know . thanks

 

Many years ago I had a '49 Rocket and my buddy had a 50 Holiday. Then he got a '54 olds and we ended installing a '50 rear end because we had plenty of 4:10 gears for the early rear, but they did not fit into the '54 housing. So I know they changed somewhere in there. It's true the '39 and up Olds and Pontiac third member were interchangeable. Old Pontiac ambulances supposedly had 4:30s. Never found one in a junk yard.

 

'49 76 isn't the "ideal" rear end, but you probably won't drive it hard enough to worry. Housings were strengthened on '50 88s due to inside rear tire wear on '49 88 cars from torque flexing. 3rd members from '49 up Pontiac 6 stick cars were supposed to have 4.30s.