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4L80E or Th400 with big block?????

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by blazen_md, Feb 9, 2003.

  1. blazen_md

    blazen_md 1/2 ton status

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    I am gonna put a 454 or 502 in my 90 k5 and I am wondering whether I should go with the TH400 or the 4L80E. I heard the 4L80E was just as strong as the TH400 but it has overdrive. I do drive my truck daily and still plan on doing so. I also take it about 2 1/2 hours away quite often to go wheelin. Overdrive would be nice but my main focus is strength. What experiences do you guys have with either one of these transmissions?? I run 38's with dana 60 front and 14 bolt rear both are locked up. So any opinions would be helpful thanks.
     
  2. 98sub454

    98sub454 Registered Member

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    The 4l80E is an electronically controlled overdrive tranny and is the strongest overdrive you can get. You will most likely need a stang alone harness for it for the tranny to function correctly (it depends on you engine setup).

    The TH400 is a strong 3 speed tranny that you wont have to do any special electronic work to it.

    The TH400 will be easier to do, but you will probably be happier with the 4L80E. I would run the overdrive tranny. I am planning on swapping a big block and that tranny eventually as well into my 76
     
  3. HarryH3

    HarryH3 1 ton status Author

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    Unless you find a smokin' deal, you're looking at somewhere in the $2,500-3,000 range for a 4L80E with harness and computer. I was talking to a tranny guy recently and he told me that he has to pay $750-850 just to get a rebuildable 4L80E core. /forums/images/graemlins/shocked.gif

    Turbo 400's can be picked up pretty cheap. $300-500 is pretty typical. /forums/images/graemlins/shocked.gif

    If money isn't a major consideration, then the 4L80E would be my first choice. But the difference in price sure would pay for a lot of fuel... /forums/images/graemlins/wink.gif
     
  4. SF87K5

    SF87K5 1/2 ton status

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    If you got a 4L80E go with it. I wish I could find one under $2000 around here. That price is for a used one also.
     
  5. 70~K5

    70~K5 1/2 ton status

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    "The 4l80E is an electronically controlled overdrive tranny and is the strongest overdrive you can get. You will most likely need a stang alone harness for it for the tranny to function correctly (it depends on you engine setup)."

    No its not the strongest overdrive auto trans you can get an allison is stonger. /forums/images/graemlins/rolleyes.gif
     
  6. 98sub454

    98sub454 Registered Member

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    if you want to get technical then i guess your right. id like to see someone put one of those in their truck. people wouldnt complain about the price of the 4L80E anymore after lookin at what that would cost
     
  7. 70~K5

    70~K5 1/2 ton status

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    Yeah, well I just had to call ya on it. I didn't say anything about the cost though. 15 years ago I knew a guy that had a 3208 CAT and a allison in a 1 ton 2wd chevy for a tow rig.
     

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