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Transfer Case Info for OEM Squarebodies

Discussion in 'Transfer Case' started by HotRodPC, Jul 16, 2012.

  1. tiredtiretodd

    tiredtiretodd Full Access Member

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    After reading a couple other threads I've come to find out that my front Dana 44 has locking hubs....(I went outside and looked.) That however, from what I've read, doesn't mean that it's part time. Am I right? Attached are a couple few photo's. What T case is this? Also Why does one of my locking hubs say Spicer and one says Ford? Either way I'll be changing those to Warn locks soon!
     

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    Last edited: Jul 28, 2014
  2. HotRodPC

    HotRodPC Administrator Staff Member

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    Does look like an NP203 to me. Someone may have put a part time kit in it if you're able to run with the front hubs unlocked. There is nothing wrong with hose hubs. Both are Spicer OEM hubs. Just that Ford wanted to take credit for the Spicer hub so they had their name put on it instead of Spicer.
     
  3. marks86

    marks86 Full Access Member

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    that is most definitely a np203 because it doesn't have that little plate with three bolts
    like this np205
    [​IMG]
    upload png
     
  4. tiredtiretodd

    tiredtiretodd Full Access Member

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    I'll probably run the 203 for a while then later put a 205. I don't drive it yet but I do know that the previous owner locked the hubs to try to put the truck in a trailer when I went to buy it. I ended up having it towed.
     
    Last edited: Jul 28, 2014
  5. tiredtiretodd

    tiredtiretodd Full Access Member

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    Yea, I looked for images so I could determine what the little plate w/ three bolts looked like but I finally ended up finding a picture of a 203 that matched mine. I do appreciate the replies because I am trying to still figure out what I do have in this truck.
     
  6. firebane

    firebane Full Access Member

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    If you have the NP203 you most likely have a TH350 transmission as well.
     
  7. Dmaxroger66

    Dmaxroger66 Junior Member

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    I'm having a problem where the truck disengages in drive and won't engage in any other gear. (Sounds like it was thrown in reverse by accident) when attempting to shift to P. Only way it engages back is by going into 4 Lo and driving forward a bit. Then I can go into 2hi again. Eventually it will grind but everything will be fine when things cool off. Mechanic says I need total replacement.
     
  8. Mike Koolhof

    Mike Koolhof Junior Member

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    Is there a foolproof way to identify the transfer case? I have a 1977 K15 Sierra Grande full time 4WD with a high and low lock, which I assume is on the front only. It has a TH350
     
  9. HotRodPC

    HotRodPC Administrator Staff Member

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    Don't Assume. It is NOT the front only. The easiest way to understand the NP203 full time 4wd is to think of the transfer case as just like a rear end differential. The wheel with less traction is always the drive wheel. Now consider your front axle as your right wheel, and your back axle as your left wheel. It's a differential. When you lock it up, then it's like a locker in a rear end where both wheels are driven and apply power.

    So if NOT in LOCK position. Your front axle might be powering the truck, or it might be the rear axle power the truck. When you go into LOCK, then BOTH axles are powering the truck.

    Yes, it's 4wd meaning, any 1 of the 4 wheels can be powering the truck unless you have lockers, then it's either the front 2 wheels or the rear 2 wheels. If you LOCK it up, and have lockers in the axles, then it's all 4 wheels powering the truck.

    Hope that helps in understanding the NP203.

    The Part time units like the NP205 and NP208 are powering just the rear axle when in 2wd. In 4wd, it's powering both front and rear axles.
     
    Last edited: Oct 7, 2019

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