Another NP203 Question

Discussion in 'Transfer Case' started by Matt Braun, Jan 10, 2018.

  1. Snoots

    Snoots Supporting Member Supporting Member

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    I've got the Dana44 in the front and a Corporate posi in the rear. So, even if both rears turn at the same rate, the front is allowed to turn at a different rate? Even if the hubs are locked?
     
  2. Honky Kong jr

    Honky Kong jr Super Sarcastic Man

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    Evidentially threw the transfer case they do. I don’t see Christian posting bullshit.
     
  3. Snoots

    Snoots Supporting Member Supporting Member

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    I didn't mean to insinuate that he was feeding me BS. What he said makes sense. I'm only trying to understand how it works.
    I've only slept 10 hours in the last 60 hours. My brain hurts.
     
  4. bucket

    bucket Super Moderator Staff Member

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    In stock form, the 203 has HI and HI LOC. HI is full time 4x4 using the diff that's incorporated into the t-case (pavement is fine). HI LOC is locked 4 wheel drive like a conventional case (do not use on pavement).

    A converted case turns the HI feature into 2wd.
     
  5. Honky Kong jr

    Honky Kong jr Super Sarcastic Man

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    I wasn’t saying you did. I’m not framiliar with the 203 I was just saying he generally knows what he’s talking about.
     
    theblindchicken and Snoots like this.
  6. CSFJ

    CSFJ Magnificent Bastard Supporting Member

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    Yeah, it's easy to see how transfer cases can get torn up. With all the different options and types of t-cases, unless you're balls deep into how these things work like we are, I can understand how the rules of operation can get confused.
     
  7. Honky Kong jr

    Honky Kong jr Super Sarcastic Man

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    Hell I’d be running a Dana 20 if the front shaft angle wouldn’t have been so severe.
     
    Last edited: Jan 12, 2018
  8. Snoots

    Snoots Supporting Member Supporting Member

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    Now I understand! Thank you! I was told once that the only 'operation instructions' for the TC were on the sticker on the visor. Mine no got. Never found any anywhere else.
     
  9. Matt Braun

    Matt Braun Supporting Member Supporting Member

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    I know I said I wasn't interested in a NP205 swap, but let's at least explore the option. I understand I need different length driveshafts due the "shorter" NP205. Is that front and rear driveshafts? What is the exact length if I am rummaging? Is there any other issues to consider in the swap? I presume there is a mounting adaptor to the TH 350 that is also different than the NP203.

    Thanks.
     
  10. CSFJ

    CSFJ Magnificent Bastard Supporting Member

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    Iirc, there was only one or two years that the 205 was found behind the th350 from the factory (1973, and 1980 iirc). I know there is a difference in spline count between the commonly found 205(either 10 spline, or 32 spline) and the th350(27 spline). What I don't know, is what the factory did to mate them together. Maybe @bucket would have more insight into what the oem did.
     
  11. Honky Kong jr

    Honky Kong jr Super Sarcastic Man

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    Isn’t there some kind of sleeve type thing in the mix on them or is it like a 208?
     
  12. Rusty Nail

    Rusty Nail Build the wall deport them all!

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    You know the guy that built the truck intended it to be full time four wheel drive. General Motors wanted it that way, the rest of the truck us intended to support THAT.

    I am nooooooo master of that stuff by ANY means BUT.

    I've had mine awhile.
    I've been HERE awhile.
    I drive mine EVERYDAY.

    From what I gather, cheap assed, stupid mother f*ckers were concerned about GAS MILEAGE and got sold the SCAM of converting their transfer case. Digest that, it's real talk.
    When their "full time" factory front hubs FAILED (think wheelspin) the cheap assed, dumb f*ck way to fix them was to put locking hubs on instead. Again, real talk.
    My case is not converted, but i have locking hubs. Between all of the involved parts, there are many possibilities of what is ACTUALLY goin on in YOUR truck.

    My advice about an NP-203 is sound. Put it in 4Hi, lock the hubs and forget about it.
    I avoid Loc but then again, i'm a city boy. My truck lives on concrete and mostly sees pavement. :imo: My truck DRIVES BETTER in 4Hi with the hubs locked. Turns out with my available installed parts, that's the way it was intended to be. No wonder I like it that way.
    I understand any "gas savings" is negligible FORTY YEARS LATER, I think you fool only yourself if you believe a conversion is going to save you any real money.

    For the record, my case sticks in Loc also, lol.

    I never, ever consider any of that stuff. I have set it and forget it.
    I have seen with my own eyes, my truck spinning all four wheels in the mud. The "open side" spins at 50% speed of the drive side, & there is a lot of stuff going on with two open differentials for sure! When it switches sides you can FEEL it. It's wild!

    Hope this helps..

    If I didn't have manual hubs installed, i'd run factory parts in a HEARTBEAT.
    But you know....previous owners...
     
    Last edited: Jan 14, 2018
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  13. crazy4offroad

    crazy4offroad Service Bullshit Filter Soon

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    Sleeve, and IIRC 27 spline. I converted my 205 from standard 10 spline to mate with the th350. Also swapped out the front driveshaft flange output shaft to one from a F*rd 205 which is 32 spline, so I could run yoke output instead of flange (like the 203) and have a choice of whatever yoke I want to run, 1310, 1350, 1410.
     
  14. bucket

    bucket Super Moderator Staff Member

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    Actually, that was just the V8 trucks. 6 cyl trucks got the th350/np205 combo through the 70's.

    It's easiest to get a complete setup from the same truck. It will all go in place of the 203 without transmission parts changes. Some years were flange front output while others were not (same for the 203). The t-case adapter uses a 27 spline sleeve. IIRC, the shifter is specific to the th350 combo as well. You can piece it all together, but it will cost a lot more. I bought two complete setups, one was only 100 bucks, I think the other was 175. That's without prop shafts, but anything that old is going to need rebuilt anyway. So new shafts aren't that much more in the grand scheme of things.
     
  15. Matt Braun

    Matt Braun Supporting Member Supporting Member

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    Appreciate the real talk. There is one thing I know is going on in my 203, and that it pops out of 4wd all the time. Credit the crappy part time kit. Nothing I can do about that at this point it was with the truck when I bought it. With all I've learned now and the use of the truck, I'd prefer the original full time 4x4. But rummaging through a bone yard for an unconverted 203 is gonna be interesting.

    There is other F-R shifting slop that I feel in the TC, but I could live with that if the darn thing would just stay in 4x4.

    And that's why I'm looking at all options.
     

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