NP231J Transfer Case - Rework needed?

Discussion in 'KJ General Discussion' started by SAString, Feb 26, 2019.

  1. SAString

    SAString Full Access Member

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    I found a bit of play in my Transfer Case rear output shaft. Now I'm venturing into the internal guts of my KJs workings.

    • Drained the Transfer case ( I used 30w synthetic last time)
      Pulled the rear shaft and boot
      Removed the Oil Slinger (PITA! Order a new one!)
      Chiseled out the seal (PITA! Order a new one!)
      Snap ring pliers or long thin needle nose to compress the large snap ring
      Expanding snap ring pliers for the smaller shaft snap ring
      Remove the extension housing bolts and housing with the bearing (break the seal by prying at the large Horns and tapping with a BFH.
      Remove the internal snap ring and tap out the bearing. (Order a new one!)
    I pulled the Oil Pump to get my first view of the t-case internals, then removed the rear cover at the pry points (Washers under the bolt heads).
    This is what my chain looks like. Is it stretched and should be replaced or is this somewhat normal?
    [​IMG]
    The dealer said $242 for the chain. Much cheaper on-line, BUT, I'm in an "If it ain't broke, don't fix it" mood.
     

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    Last edited: Feb 26, 2019
  2. Tog

    Tog Full Access Member

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    Following

    Sent from my SM-G960F using Tapatalk
     
  3. LibertyTC

    LibertyTC Well-Known Member Staff Member Moderator

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    In the factory service manual diagrams of the NP231J, the chain droop appears to be comparatively normal.
    If the chain was really drooping, it would probably be making contact & grinding the inside case away.
     
  4. mrlavalamp

    mrlavalamp Full Access Member

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    maybe take the chain off and measure total length flat and pulled tight.

    Compare that to the pin to pin lengnth to see if it is stretched.

    Most chain is designed to wear up to a certain % stretch and then the risk is after that point it will not carry the full rated load anymore without possibly breaking.

    I am no chain expert, but industrially we replace most of our chains when they get to 5% stretch, some equipment has specs that require it sooner though. Not sure if the same applies to the chain found in our T-case though, so definitely need to do some searching in the manual to see.

    EDIT: found this from diamond (one of the better chain mfr in my experience).
    https://www.diamondchain.com/understanding-wear-life/
     
    Last edited: Mar 8, 2019
  5. JoeLinn

    JoeLinn New Member

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  6. dillon

    dillon New Member

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