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TH400 to NP241

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by Cruz89K5, May 15, 2006.

  1. Cruz89K5

    Cruz89K5 1/2 ton status Premium Member

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    Didnt find anything while searching, so I'm wondering if it can be done. I like my 241 that is behind my 700r4 but I am going to a th400 and really dont want to loose my low range. Is this doable? What about buying a 2wd th400 and changing it over to a 4wd unit? Sorry for the ignorance.
     
  2. TEXICAN

    TEXICAN Registered Member

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    why dont you just beef up the 700R4, that what im doing right now unless you don't care about having a 4th gear.
     
  3. Cruz89K5

    Cruz89K5 1/2 ton status Premium Member

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    Done once, tore it apart in less than a year behind a tired 383 and a truck on 33's. It's not getting DD'd anymore, and in overdrive it only got in the neighborhood of 9mpg at highway speeds. How can a 700 be built to handle a truck that gets ran hard? I just dont want to waste my money again and end up with a very expensive boat anchor. Thanks.
     
  4. TEXICAN

    TEXICAN Registered Member

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  5. TEXICAN

    TEXICAN Registered Member

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    o yeah what parts have u had break. You can order so many beefier parts. I currently rebuilt mine minus the valve body still waiting on parts. I ordered top of the line Blue clutches and few other parts.
     
  6. cbbr

    cbbr 1 ton status GMOTM Winner

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    Are you asking if you can get a th400/241 combo? if so, yes. That is the stock setup in my Burb.
     
  7. Masiony

    Masiony 1/2 ton status

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    yeah, its a factory setup. BTW, what years or applications came with a 400 and drivers drop 241? i am looking for that combo to replace my 700 eventually. not that i will break the 700, but i want the security of a 400. that and the fact that OD is over rated.
     
  8. Cruz89K5

    Cruz89K5 1/2 ton status Premium Member

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    I havent been into it yet, but there was a really really hard 1-2 shift, it kept pulling until I stopped, then nothing. Still has reverse, but it fades away after warming up. Had a HD converter and clutches, transgo stage 2 and corvette servos.
     
  9. TEXICAN

    TEXICAN Registered Member

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    Hey i have a 700R4 Tech manual i hook you up. I was in your situation I spoke to my instructor at my tech school and told him i wanted to put my 700R4 being a 300-350 hp 350. Which i have at the machine shop. He said it was doable. Im went all out on cluthces, very pricey. A couple things reccommended to me. Were a new Beast Reaction sun shell, you need to chekc the in play on input and reaction carries. New sun gears. I bought the top of the line cluthces. Replaced my bearings. Pain in the ass if you dont have the right tools. Defenitley need a tranny cooler. You dont have to get the blue clutches. I would reccomend ordering the tranny manuel for your tranny. there only like 17 bucks. Email these guys on the internet ask them what they reccomend and compart between them.
     
  10. Hossbaby50

    Hossbaby50 3/4 ton status

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    If it isn't a DD or the like ditch the 700R4 and never look back. The TH400/208 or 241 is a stock setup in late 80's trucks and military trucks.

    Your current 241 will not bolt up to a th400, you will need to swap in a 32 spline input gear. A 700R4 has a 27 spline input gear.

    Just get a TH400 (208 or 241 version) and the adapter for it. Swap your input gear in your 241 to 32 spline. There are other little things to find out about. Is the flexplate the same or do you need one from the Th400 setup too. Will your current crossmember fit? etc.

    I have killed more then my share of 700R4's (stock and built) and there is a Th400 sitting in my garage waiting on the 700R4 in my K5 to die. Then the Th400/208 combo is going in.

    Harley
     
  11. wayne

    wayne 3/4 ton status

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    I have done the swap 2 times. Not hard at all to do. Finding the 32 spline input at a decent price is that hardest part. I am going to a doubler sometime in the future and will be selling most of my th400/241 stuff.
     

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