Difficult to add a posi unit in my rearend?

Discussion in 'Transmission & Driveline Topics' started by bondora68, Mar 11, 2021.

  1. bondora68

    bondora68 Veteran Member

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    So, I am a very handy guy and have restored several Camaros including engine work. I have never, however, done any real rear end work... How difficult is it to install a posi unit in my 71?
     
  2. BonzoHansen

    BonzoHansen Administrator Lifetime Gold Member

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    Search this forum (Transmission & Driveline) for a number of write ups. IMO its not that hard but it does required some tools you may or may not have, like a press.
     
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  3. big gear head

    big gear head Veteran Member

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  4. bondora68

    bondora68 Veteran Member

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  5. bondora68

    bondora68 Veteran Member

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    Found this...Looks pretty simple.
     
  6. bondora68

    bondora68 Veteran Member

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  7. big gear head

    big gear head Veteran Member

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    Yes, you have 28 spline axles. If you remove the axles and find that they are worn where the bearings run on them then you will have to replace them. When you replace them you might as well upgrade to 30 spline axles and a 30 spline differential. The cost is pretty much the same and you get 30% stronger axles.
     
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  8. bondora68

    bondora68 Veteran Member

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    So, what happens if the backlash you measure after the new diff install is more than the starting backlash measured? Can anything be done? What's the point of measuring?
     
  9. big gear head

    big gear head Veteran Member

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    You have to shim it. All of them are shimmed to get the backlash and bearing preload correct.
     
  10. TTR230

    TTR230 Veteran Member

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    This video is a pretty good basic tutorial on replacing an open with an posi. It's not on a Camaro specifically, but same enough. I was pretty intimidated with the idea of swapping diffs, but it relatively easy.

    By the way, this guy has lots of really excellent videos on all manner of vehicular repair and rebuilding subjects.

     
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