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What Transmission?

Discussion in 'The Garage' started by mikeperez22, Jun 18, 2004.

  1. mikeperez22

    mikeperez22 Registered Member

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    I'd like to update my 72 TH350 tranny to a 4 speed auto. What are my best options? I'm going to hook it to a built 400.
     
  2. big83chevy4x4

    big83chevy4x4 3/4 ton status

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    700r4 or a 4L80E

    the 4L80E is more expensive, plus you will need a controller, but you will never have a problem with it.

    the 700r4 can be built to live behind that motor, but it'll cost a lost of money to make it survive.
     
  3. smokkey1

    smokkey1 1/2 ton status

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    or you can get th400 pretty bulletproof if you don't mind a 3 speed. But if you want od go with the 4l80E.
     
  4. sled_dog

    sled_dog 1 ton status

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    a 700r4 will do fine if built well by a respectable company. A built anything in front of a stock automatic is almost always a bad choice in my mind. But I hate autos...
     
  5. mikeperez22

    mikeperez22 Registered Member

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    Will the 700R4 require any modifications other than the input shaft to the NP205? I've read about a few people moving their engines forward a few inches. I'm not sure why?
     
  6. 84_Chevy_K10

    84_Chevy_K10 Banned

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    You will not need to modify your input shaft, it is already 27 spline.

    You will need to either swap output shafts in the transmission or use a spacer to hook them up.

    No matter what you do, you're going to need to make your front shaft longer and rear shaft shorter as the 700R4 is longer.

    No need to move the engine at all.
     
  7. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

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    [ QUOTE ]
    I'm going to hook it to a built 400.

    [/ QUOTE ]I have a built 406 in front of a built th700R4 and I love it. /forums/images/graemlins/waytogo.gif
     

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