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GM 400 to a Ford 205

Discussion in 'The Garage' started by b454rat, Mar 14, 2006.

  1. b454rat

    b454rat 1/2 ton status Premium Member

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    How do you put these two together?? I have a 4wd version of a 400, as well as a 2wd. From what I've read, all Ford 205s are the same. Anybody have any info?
     
  2. sweetk30

    sweetk30 professional hooker Premium Member

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    i think its round adaptor and swap to a gm 32 spline input gear. but dont recall if its the short or long input.
     
  3. tarussell

    tarussell 1/2 ton status

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    Change the in-put gear to a GM 32 spline and talk with your custom adapter maker about which TH400 output shaft length to use. Note: there are two length 32 spline 205 input gears also so discuss that with the ones making your adapter.
    I would think NWF could get you all set up.
    The Ford 205's do use a round adapter but it is different than what GM used. Might be able to redrill the Ford case and use a 1985 on up GM adapter and long input gear ???


    Tom
     
  4. b454rat

    b454rat 1/2 ton status Premium Member

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    I have the newer (86) 400/205, sitting outside. The trans is corroded and has two ears broke off. What sucks is I don't have a Ford case here or I could figure out what I would need. I might just go with a divorced Ford 205, then I wouldn't have to change any driveshafts, as my truck now has a div Dodge 205. Might not even worry about it. If I sell my GM 60, then I would use my HP60, then I would have to figure out the t-case thing.
     
  5. steve_kibbe

    steve_kibbe 1/2 ton status

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    I asked the same question before, and the results I got back were the th400 adapter to the round gm np205 will fit the ford np 205 case. I believe the long input from the chevy case is needed.

    I have a ford case, the round adapter and the long input shaft, I'll have a look tomorrow and post back up.

    I'll also see if I can find the thread I posted.
     
  6. steve_kibbe

    steve_kibbe 1/2 ton status

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    I ttt'd the post I made, I'm on a friends comp and don't know how to copy and paste on a mac:rolleyes:
     
  7. b454rat

    b454rat 1/2 ton status Premium Member

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    That would be cool, appreciate it. Like I said in my last post, not sure what I'm gonna do. I was gonna go with a 4-speed, got all the pieces, but then opted to stay auto, that way I can just bolt it in.
     
  8. u2slow

    u2slow 1/2 ton status

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    The Ford input is closest in length to the short 32-spline input.

    In theory, you should be able to use an 80's TH400 w/NP208 adapter... because a 208 (or 241) is very close for the input length. Just notch for the shift rail. Also, since the GM bolt pattern has a bolt at 6:00 and 12:00 postions, you get some clocking for free. :D

    [​IMG]
     
  9. b454rat

    b454rat 1/2 ton status Premium Member

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    I can get one of those adaptors too. I will have to get my hands on one and see what happens. Now all I have to do is get to my buddy's yard which isn't open on weekends....Thanks for the help!!
     
  10. tarussell

    tarussell 1/2 ton status

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    I had no idea that the GM and Ford pattern were the same . That is GREAT ! The conversion's just keep getting easier.

    Tom
     
  11. MEK5

    MEK5 1/2 ton status

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    You can put a 32spline input in the Ford case which one (short/long) will depend on the 400 output lenght.Since the 86 400 you have is junk you can use the 2wd with a shaft stickout of 4 1/2" with a short 32spline input.

    The bolt pattern on the round pattern GM and Ford cases are the same but the hole spacing is not symetrical which will cause problems with using a GM adapter.I messed with this a couple years ago and my memory is not what it used to be and I HOPE IM WRONG but the GM adapter is not a bolt on deal with just a rail notch.You need to look at that part alittle closer because the hole spacing is off just enough to ruin your day!

    I just spent alot of time with 208 adapters and 205s and determined that it can be done but!
    The 208 adapter is only 2 1/2" wide vs 4" with the 205 adapter so this causes clearance issues with the 205 idler shaft/nut on the front of the case as well as the mount hitting.This is using the short foot adapter,so I tried the early tall 208 adapter which solved the mount problem but not the idler shaft hit unless the case was clocked up.The 208 TH400 has a shaft stickout of 2 3/8- 2 7/16 and with the short input gear you only end up with about 1 1/2" spline contact which would probably work ok but I would like to see the full 2" contact but Im no engineer!
    I did fiquire out that I could use the tall 208 adapter with the LoMax hooked to a 4L80 because I could clock the transfer up and the transmission output was longer which gave me full spline contact.

    IMG00004.jpg

    IMG00005.jpg
     
  12. u2slow

    u2slow 1/2 ton status

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    Looking at NWF's Ford/GM dual-patterned adapter plate, you can see two holes are a little closer together than the rest. At least one patern must not be symmetrical. Probably only have to 'ovalize' one hole to make it work ;)

    [​IMG]
     
  13. Greg72

    Greg72 "Might As Well..." Staff Member Super Moderator

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    If you decide to go with the high pinion setup (Ford side) and have a Doubler in your plans, I've got a brand new ORD kit that I don't need anymore.... :deal:
     
  14. NorthWestFab

    NorthWestFab 1/2 ton status

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    The GM Round and Ford Patterns are the same BUT they are rotated away from each other at 77degrees, so you will not get a clean direct swap.

    5 of the 6 holes are spaced the same, with 1 wider on each pattern, so it is possible to 'hack' it together, round out some holes, but I don't recommend it. We have the resources to mate a Ford NP205 to a 32 spline TH400 cleanly and correctly.

    -Kyle
    NWF.
     
  15. u2slow

    u2slow 1/2 ton status

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    :confused: I must be missing something :confused:

    I can't see a 6-bolt round pattern being out more than 30* left or right. :thinking:
     
  16. b454rat

    b454rat 1/2 ton status Premium Member

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    And I thought this was gonna be easy. I wouldn't mind a doubler, but the money thing is the major factor right now, I don't have any!! I thought I might have my D60 sold out of my truck, but I need to keep the GM outers to put on the HP so I can run the 40x15" boggers I just got. Buyer wanted to do the same thing. I don't think I will do the SAS on my 97 for a while if it all, so I figure sell the GM60 and use the HP60. I *might* have two more HP60s available to me, IIRC they are the newer style, 88-92. If I do go with the HP60, think I will use a div Ford 205, that way I won't have to get new driveshafts, again, and have to worry about hooking the case to the trans. I can sell the 400/205 and recoupe some of the money to get the truck to use the the trans/case. I talked to a welder about the ears and the corrosion, he said that it's a pretty easy fix. The fluid in the trans looked really good, was still red, not burnt. I need to sell some stuff so I can get the other 2 boggers.....Who needs some stuff??
     
  17. NorthWestFab

    NorthWestFab 1/2 ton status

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    Although each hole spacing is less the assymetrical pattern is out by 70 odd degrees. This is if you were to not open any holes up.
     
  18. b454rat

    b454rat 1/2 ton status Premium Member

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    Back from near death, but how much would this adaptor/mod be??
     
  19. NorthWestFab

    NorthWestFab 1/2 ton status

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    Depends what tailshaft the TH400 is - is you use the short version originally coupled to the NP203, it would save a few bucks as the adaptor is thinner, you'd be looking at about $269 for the adaptor. Let me know if you have a longer tailshaft version (looks like the 205 version from reading the above post) and I'll generate a quote.

    You'd need a new inpuut gear and to adress shifters, all of which we can provide.

    -Kyle.
    NWF.
     
  20. b454rat

    b454rat 1/2 ton status Premium Member

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    I have the 4wd version of the 400, as well as the adaptor and 205 off the 400. I know I can take the input off the 400/205, and put it in the Ford 205. But how much fab'n to hook the Ford to the 400?? Linkage isn't a problem....
     

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