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Doug Nash overdrive adapter SM465

Discussion in 'Manual Transmission & Clutch' started by 1984dually, Dec 28, 2020.

  1. 1984dually

    1984dually Full Access Member

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    Got a couple of units and want to bolt them to a sm465. Anybody got a line on one or maybe trans with one on it?
     
  2. 1984dually

    1984dually Full Access Member

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    Information for anybody that wants to know. Doug Nash units will bolt to the factory 208 trans adapter. Bought a 4x4 sm465 with the 31 spline output shaft and it bolted right up. 60E6A5F6-A67B-4227-9B70-242801C00E94.jpeg
     
  3. bucket

    bucket Super Moderator Staff Member

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    Do you by chance mean 32 spline? So if it bolts up to the 465, then it should also bolt up to a '81-up 4x4 TH400 that had a 208 or 241 hanging off of it.

    So where do you find these Doug Nash units anyways? Motorhomes?
     
  4. Turbo4whl

    Turbo4whl Supporting Member Supporting Member

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    What is the overdrive ratio of that Doug Nash unit? Do all the units have the same ratio? Thanks.
     
  5. 1984dually

    1984dually Full Access Member

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    32 spline is correct(fat fingers). See no reason it wouldn’t work on th400 with the correct transfer case but never tried. Doug Nash/us gear units can be found behind most anything. Come in both overdrive and underdrive ratios(20%). All gear driven with a 35000 gvw rating. Shifts just like a 2 speed rear axle.
     

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