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4LE80 -'87 Sub 3/4 ton 203 FullTime TCase?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by uglytruk, Dec 26, 2006.

  1. uglytruk

    uglytruk 1/2 ton status

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    4LE80 in '87 Burb 6.2 w/Full Time 4x4?
    I'd like to convert my 3/4 ton Sub to full time 4x4, not part time, as the 208 only permits 4 wheelin' on slippery surfaces. Overdrive would also sure help with the stupid 4.10 gears!
    The 4LE80 has the same tail bolt pattern as my TH400, as opposed to the 700R, which more closely resembles the TH350, but I want to use the '73-'79 203 iron Tcase. These usually came with the TH350, like mine. I like the idea of being able to keep it in 4 wheel on dry pavement as the 203 has the center diff. Great for plowing when the streets are dry!
    So 6.2-4LE80-NP203-
    I've spoken with Vince at www.4xheaven.com in Gloversville NY. He seems to know his stuff, but I want to hear from others before I act.
    The 4LE80 will also require a stand alone computer. Sheesh...

    Anybody ever do this?

    Thx, Andrew
     
  2. uglytruk

    uglytruk 1/2 ton status

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    Here's a few pix... THE 3/4 Sub, 1/2 ton PU w/305-700R4-208-3.08's(?), 85 3500 SRW 6.2-TH400-205(?)-4.10's

    More lifted Sub-3500 004 (Large).jpg

    More lifted Sub-3500 001 (Medium).jpg
     
  3. muddybuddy

    muddybuddy 3/4 ton status

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    im going to be running a similar setup on my truck once i get the tcases built
     
  4. uglytruk

    uglytruk 1/2 ton status

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    OK, I wuz rong. The 4 speed must've been dropped in '86ish, I thought it was never available in 20 series. MY bad!
     
  5. k204dr

    k204dr 1/2 ton status

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    is your 87 fuel injected or carbed? if its injected, you need a wiring harness from a 91 suburban 3/4 ton. if carbed, then you need one from a 91 suburban diesel, or even a 92-93 truck with diesel. the diesel had a standalone controller until 94.
     
  6. k204dr

    k204dr 1/2 ton status

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    ha, reread that you're gonna run a 6.2. i'm using a 93 1ton diesel harness for my swap. just need to get the wiring harness sorted out, and get my buddy to finish building the trans. You'll also need to machine the adapter a little to fit the 4l80. I guess its a little different where the seal is in the adapter. I'm using a 2wd HD case, so I can use both speed sensors in the case, and still run my speedo off the transfer case.
     
  7. uglytruk

    uglytruk 1/2 ton status

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    Yeah, 6.2. the 4L80 thought was 'cause the transfer case guy was trying to convince me to keep the 208. No way, I want FULL TIME 4WD. The 4L80 resembles the TH400, therefore easier swap, even though I have a lo miles 700R4-208. Buying an Advance Adapters output shaft to mate the 700 to the 203. (Cheby never attached the two).Check their web site. A couple paragraphs tells so much! Check p.40 and on>>> WOW http://advanceadapters.dirxion.com/?screen=1280&os=win
     
  8. Confedneck79K30

    Confedneck79K30 3/4 ton status

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    you do know, that if you put a 208 into 4hi, it is in 4wd, you really want to drive around in 4wd on the pavement all the time? i mean why? a 208 is a great tcase, if you dont like the idea of the chain, then go 205...
     
  9. uglytruk

    uglytruk 1/2 ton status

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    Yup, 4wd ALL THE TIME. I plow snow in the city, so driveways are obviously full of snow, then on salted/dry road, then up hill in snow, around driveway and out the other side on dry road, turn corner and re-enter property. I'll make a video so you can see.
    So what does this blab mean? Because the d-train tightens up, I should/do put it into 2 hi, then 4 hi, then weak 305, so 4 lo, it's a pain. And I go round and round the drivethru parking lot 10 times to get all the snow. Then down the street to the other one, and same routine. A video speaks it all, keep watching this space, I plowed yesterday... Or got to www.youtube.com, here's the link. Click "see all videos", to see the parking lots we modified this summer to be able to enter one side and exit the other. Lot easier than reversing! And SUBSCRIBE!
    So if I had full time 4wd, I'd leave it in 4hi, and drive... And then there's snowdrifts accross I87 from Montreal. Better to hit them in 4wd than slow down and pull lever back, don't ya thunk???

    http://www.youtube.com/watch?v=tIsDBD6un8Y&mode=related&search=
     
  10. Confedneck79K30

    Confedneck79K30 3/4 ton status

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    ehh snow, blahh.. its florida, we have water on the roads lol... i understand now, so does the truck sit during the summer months?
     
  11. uglytruk

    uglytruk 1/2 ton status

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    Here's the latest wreck...Anybody need some Harley stickers???

    83 3/4 Ton, was 6.2 700R4, now 350, TH400...

    1 5 07  83 3 4 ton  Sub floor repair 007.jpg

    1 5 07  83 3 4 ton  Sub floor repair 001.jpg

    1 5 07  83 3 4 ton  Sub floor repair 010.jpg

    1 5 07  83 3 4 ton  Sub floor repair 015.jpg

    1 5 07  83 3 4 ton  Sub floor repair 013.jpg
     
  12. uglytruk

    uglytruk 1/2 ton status

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    Aren'r ya jealous I found it before you???

    :eek1: Don't tell me wife! :mad:

    Plow not included, but look what's hiding underneath... a couple 208's... interesting...

    1 5 07  83 3 4 ton  Sub floor repair 011.jpg

    1 5 07  83 3 4 ton  Sub floor repair 016.jpg

    1 5 07  83 3 4 ton  Sub floor repair 022.jpg

    1 5 07  83 3 4 ton  Sub floor repair 018.jpg

    1 5 07  83 3 4 ton  Sub floor repair 017.jpg
     
  13. uglytruk

    uglytruk 1/2 ton status

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    Like those HD front spring...

    'll put 'em on '87 Sub 6.2...

    1 5 07  83 3 4 ton  Sub floor repair 014.jpg

    1 5 07  83 3 4 ton  Sub floor repair 020.jpg

    1 5 07  83 3 4 ton  Sub floor repair 023.jpg
     
  14. beater_k20

    beater_k20 Banned

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    uh... having a 203 truck that i use for plowing, i'd kill for a part time case. probably going to go 400/205 when i restore it. why do you want to swap backwards? it wont kill the 205/208/241 to drive it on dry pavement a little. :dunno:
     
  15. imiceman44

    imiceman44 1 ton status

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    It actually will, it stretches the chain.
     
  16. uglytruk

    uglytruk 1/2 ton status

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    Yup, Iceman's right.. You can feel the drivetrain tighten up, big time...
    Coming soon, a link to youtube showing me plowing...
     
  17. uglytruk

    uglytruk 1/2 ton status

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    I'm confoosed... Aren't the 203 and 205 diffy equipped? Just chain on 203 and gear on 205? The chains more than adequate for my limited use, and I just bought a 205 equipped partz truck... See pix above...
    What's so bad about your 203?
     
  18. imiceman44

    imiceman44 1 ton status

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    205 has no diff.
    The only GM case that has a diff is the 203.
    Maybe one of the new NVG tcases might also like the one in the escalade, but those are driverside drop:D
     
  19. uglytruk

    uglytruk 1/2 ton status

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    So bought the Redneck truk for other parts, thought 205's had diff as well, oh well. Makes sense, 203 was used w/out lockable hubs, hard to believe... locked 24/7, sheesh...
     
  20. imiceman44

    imiceman44 1 ton status

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    Don't dismiss that 205, it is a nice Tcase and I am sure you will find someone that wants it.
    :D
     

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