12 bolt id

Discussion in 'Transmission & Driveline Topics' started by jb, Aug 29, 2016.

  1. jb

    jb Veteran Member

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    can anyone id this 12 bolt for me
    23833X
     
  2. big gear head

    big gear head Veteran Member

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    Look for the code stamped into the right axle tube. It should be facing the front.
     
  3. jb

    jb Veteran Member

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    thanks but I only have the posi and ring gear but I did find out it is a rare 12 posi unit with a 3:31 ring gear from a 65 chevelle ss 396
     
  4. Gary S

    Gary S Administrator Lifetime Gold Member

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    If it is a posi unit, it can't be from a '65 SS396. Techically there was no '65 SS396 Chevelle. It was designated a Z16 instead. And, the Z16 was not available with posi.
    The SS396 designation showed up in 1966 for the Chevelle, and for the Camaro and Nova in 1967.
    The 12 bolt posi 3.31 was available in the small block Chevelles starting in '65 along with the Full size cars and from there all the way to 1970 in Camaro, 1971 in Nova, and 1972 in Chevelle. Your posi carrier could be from any one of those cars.
    There should be a date code on the ring gear to determine what year it is.
     
  5. Smokin'Joe

    Smokin'Joe Veteran Member Lifetime Gold Member

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    ( Is it just me, or do I hear this being read in Marissa Tomei's voice from My Cousin Vinny )



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  6. Dave Nelson

    Dave Nelson Veteran Member

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    That's good !!!!! LOL
     
  7. big gear head

    big gear head Veteran Member

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    Gary is right, the Z16 wasn't available with the "posi" rear end. Seems crazy, but that's how it was. It could be from a '65 Impala or a 327 Malibu SS. Anyway, it's going to be a 3 series "posi" if it has a 3.31 ring gear on it. Too bad you don't have the pinion to go with it.
     
  8. jb

    jb Veteran Member

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    it is a date coded z16 ring gear i assumed the diff was with it
     
  9. jb

    jb Veteran Member

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    ah the batch of parts i got it with came with a 65 impala center console!
     

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