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Sm420 T Dana 18 Plate Adapter?

Discussion in 'Early CJ5 and CJ6 Tech' started by Mr Vaughan, Feb 8, 2021.

  1. Feb 8, 2021
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
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    For the junkyard swap, you need the transfer case adapter and main shaft. This has been discussed a lot in older posts. Any Jeep or IHC T-18 will work. These parts are then used to build a Ford T-18 that accepts the Dana 18 on its tail.

    JMO - if you want to do this cheap, you need to understand the subject and be ready to buy the right parts as they come along. Do your homework and be ready.
     
  2. Feb 8, 2021
    Mr Vaughan

    Mr Vaughan

    rich, you got a link to that trans/tcase?
     
  3. Feb 8, 2021
    boopiejones

    boopiejones I can’t drive 55

    California east bay
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    yes I have a 198 with an sm420 and d18. I checked thru the stuff that the PO gave me and there wasn’t as much as I thought.

    I think the first image has something to do with the conversion, but I’m not 100% sure. Second image says they lengthened the front driveshaft and shortened the rear both by the same amount... 3 and 7/8 inches 93493319-B273-4302-B52E-D5B3A02BCD10.jpeg 98423E44-9AE0-43F3-A189-B7379A631CCD.jpeg
     
  4. Feb 8, 2021
    Rich M.

    Rich M. Shoe salesman 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Maryland
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  5. Feb 8, 2021
    ITLKSEZ

    ITLKSEZ Hope for the best, prepare for the worst

    Liberty Lake, WA
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    I can’t believe that’s still up.
     
  6. Feb 8, 2021
    Jw60

    Jw60 Sitting up n buckled down. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Sedalia MO.
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    T
    And Gone
     
  7. Feb 9, 2021
    Mr Vaughan

    Mr Vaughan

    too bad, gonna have to look more.
     
  8. Feb 9, 2021
    Rich M.

    Rich M. Shoe salesman 2024 Sponsor 2023 Sponsor 2022 Sponsor

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    Huh I can still see it, or is it in Sedalia now? :cool:
     
  9. Feb 9, 2021
    Rich M.

    Rich M. Shoe salesman 2024 Sponsor 2023 Sponsor 2022 Sponsor

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    Long input Waggy /truck T18's show up several times a year on my local marketplace. I can convert one to short input for less than $200.
     
  10. Feb 9, 2021
    Mr Vaughan

    Mr Vaughan

    you can probably still see it if you don't reload the page, try that.
     
  11. Feb 9, 2021
    Mr Vaughan

    Mr Vaughan

    i wish we had that kinda stuff around here.
     
  12. Feb 9, 2021
    ITLKSEZ

    ITLKSEZ Hope for the best, prepare for the worst

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    That’s what I did. :bananatool:

    [​IMG]
     
    fhoehle, Rich M. and Fireball like this.
  13. Feb 9, 2021
    Jw60

    Jw60 Sitting up n buckled down. 2024 Sponsor 2023 Sponsor 2022 Sponsor

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    Not me but there is a "guy" in Columbia Missouri that likely has a jeep t18 in his "yard". I was all narrow ratio t18 until I heard about the tera low gear shortage. Now I'm holding on tight to my sm465 in the garage. The gear range on the sm465 isn't ideal but I haven't snagged a t18 of any sort. I already have the clutch for an sm465 and it's "right" for an 85 engine.
     
    Last edited: Feb 9, 2021
  14. Feb 10, 2021
    Mr Vaughan

    Mr Vaughan

  15. Feb 10, 2021
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

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    Price is ok, not great IMO. I don't think the T-18 was available in the 4.02:1 first gear ratio. 4:1 is ok, but not the granny gear you want. The SM420 is something like 7:1. The T-19 definitely was available in the 4;1 ratio, but if this is actually a T-18, then I'd presume it's 6.32:1. The seller shows a tag; try researching the numbers. Maybe ask on a friendly Ford pickup forum?

    I would keep looking for a Jeep T-18. Your greatest asset is time to wait for a suitable transmission. Ford made something like a million light trucks annually, while Jeep's output of J-trucks was likely 1/100th of that.

    Read old posts and make yourself an expert. Then you can pounce on that deal when it comes around.
     
    Last edited: Feb 10, 2021
  16. Feb 10, 2021
    ITLKSEZ

    ITLKSEZ Hope for the best, prepare for the worst

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    That’s an NP435.
     
    timgr and 73 cj5 like this.
  17. Feb 10, 2021
    Mr Vaughan

    Mr Vaughan

    so i'm looking for a J truck tranny? i think i know a guy with one of those, unsure of wether it's 2 or 4 wheel drive. he might not wanna part with it tho.
     
  18. Feb 10, 2021
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

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    Any T-18 from a 4WD Jeep except a 1980 or newer J20. 2WD J-trucks existed in the first half of the 60s, but not many. IHC too, though they are weird. Either can be taken apart to convert a Ford 2WD T-18 to work with a Dana 18 or Dana 20.

    The J-truck or Wagoneer T-18 can be used complete with some added parts. I'm not going to feed this to you - do your homework.
     
    Jw60 and jpflat2a like this.
  19. Feb 10, 2021
    Bigdaddy13

    Bigdaddy13 Member

    So.Cal
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    This is one of the many reasons I'm going with an sm420. One tranny and one adapter. Find an SM420? It fits, no matter what. There is an older vs. newer version, but they both fit the same.

    Every time i researched T18's my head started spinning. LOL.

    I'm really not expecting any rear drive shaft issues, since many other folks have done this swap. BoopieJones has the exact same drivetrain as what I'll be going to, for example, and there's several CJ2A/3B's that I've heard of with the SM420/D18 setup. (and they're even shorter, OAL-wise)

    I also have been researching a modern 4 cylinder or V6 motor swap, and either an AMC/Jeep or Chevy motor will bolt right up to the SM420 with nary a hick-up.

    "SM420's are getting long in the tooth and some parts are rare/hard to find" - I get it, but my transmission is going to be completely rebuilt when i get it.
    1. Even if parts wear out in, say, 100k miles, that's like 20 years of usage at my current miles-per-year rate.
    2. SM420's are COMPLETELY overbuilt for this size vehicle. Part's breakage is just not a concern of mine.

    Just food for thought, Tyler.

    If you like the parts search/hunt - go for it. Personally I like jeep'ing more than I like wrenching or parts hunting. :)
     
  20. Feb 10, 2021
    Jw60

    Jw60 Sitting up n buckled down. 2024 Sponsor 2023 Sponsor 2022 Sponsor

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    Tyler, Tim did a "4 speed transmissions as I know it" thread not to long ago to sum up everything. I would save that page when you find it.
    Also read up on the Novak knowledge base. There is a lot of info there.
    Think of this as a research project.
     
    Bigdaddy13 likes this.
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