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Swapping 3.70 gears for my 4.11's???

Discussion in '40- & 55-Series Tech' started by Roberto, Feb 26, 2007.

  1. Roberto

    Roberto SILVER Star

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    Does anyone know if 3.70's third members can be swapped in place of my 4.11's in my 83 BJ42 with full floaters? The 3.70's are from a 87 FJ60 with fine spline like mine I believe. I dont know if the full floating thing really matters?
     
  2. cruiser_guy

    cruiser_guy

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    Yes, you can do that as long as they are not limited slip or locked going into a semi floater. You will need the "C" clips and pin from the 4:11 in the rear if you are a semi floater and you won't need it if you have a full floater.
     
  3. Roberto

    Roberto SILVER Star

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    Mine are full floaters so I wont need anything? Is this an easy or hard swap? I thought I read it was easy on FF's?
     
  4. Josie'sLandCruiser

    Josie'sLandCruiser Stop calling it a "FJ."

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    Hi All:

    Yes, this should be a fairly easy swap. You need to ensure that the bolt patterns on the pinion flanges of the donor 3.7 ratio third members match your BJ42 driveshafts.

    Regards,

    Alan
     
  5. Poser

    Poser Oh...Durka Durka Durka. s-Moderator Supporting Vendor

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    The companion flanges on the 87-60 series diffs are not going to be the same as the ones on your 83-BJ42. You will need to swap the flanges over.