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Thread: Transfer Case?

  1. #1

    Default Transfer Case?

    I'm looking to replace my transfer case SOON, like before next weekend soon when me and K go to Mississippi and I need to know some stuff. I am finding a few transfer cases but I am stumped to actually which one will fit and work in the truck. I know its a New Process 246 with a 2.72 ratio but I'm being told that I may also have the PO; NP8 which is AutoTrac 4WD. Kinda stumped on what I have and I can't look since the glovebox in the truck is from a different truck. My dad also says that there are 4 different transfer cases that they used for my year.

    The tag on the back of mine says NP246; 2.72 Ratio

    I am finding manual shift transfer cases from 99s online used for a decent price and would like to know if I can fit this in the truck or do I need one that is push button shift.

    Is there something I can use to look up the VIN and determine what POs I have?

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  2. #2


    If you have a push button shift transfer case you need to replace it with a push button. There are some vin checkers out there but they aren't always accurate.

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  3. #3


    If the tag on your t-case says its a np246 then the t-case you need to get to replace yours has to be a np246. Why are you replacing the t-case?

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  4. #4


    I had that break through while talking to @nakranij earlier. The bearings on the shafts are out and its sounding like there are some werewolves in there at high speed and I now have a nice little vibration in the gas pedal.

    Turns out its PO NP1.The thing that confused me was my dad telling me there were 4 different cases used on 99s when in fact I think there are just 2 different ones; auto trac (PO NP8 (New Venture)) and New Process NP246 (PO NP1)

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