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Another dumb diff question........sigh...

Discussion in '40- & 55-Series Tech' started by 1Fine40, Jul 12, 2005.

  1. 1Fine40

    1Fine40 Rust Buster SILVER Star

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    I know that the front and rear diff on the FJ-40 are virtually the same. You can swap a front for a rear. BUT, do you need to reset the pinion depth or backlash? I mean, in the front the pinion is driving on the coast side of the ring gear, and on the rear the pinion is on the drive side..... What say the gear gurus out there?
     
  2. nuclearlemon

    nuclearlemon not an addict Moderator

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    nope...just need to swap the center block from the rear diff into the front when you swap.
     
  3. 2badfjs

    2badfjs

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    is'nt that the other way around.
    the front diff does'nt use the block, the rear only. or am i wrong?
    because if i'm wrong, and the front uses the block, you may have help me figure out my problem ige! :eek: :doh:
     
  4. ken_79-fj40

    ken_79-fj40

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    The rear definately uses the block. I haven't torn into my front yet. One of these days i'm going to service my knuckles.
     
  5. honk

    honk

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    You won't need to open your front differential to service the knuckles, it doesn't use the 'c' keepers. The axles are kept in at the hubs instead.
     
  6. FLFJ40

    FLFJ40

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    Rebuilding the knuckles is really alot easier than it looks in the manuals. I am rebuilding mine right now and the hardest part is getting 35 years of grime off of them.
     
  7. nuclearlemon

    nuclearlemon not an addict Moderator

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    yeah...it's kinda confusing wording, but when you put the front diff in the rear, you'll need to pull the block from the rear and put it back in the rear with the new rear diff (i.e. your old front diff).
     
  8. 1Fine40

    1Fine40 Rust Buster SILVER Star

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    Thanks for clarifying this for me. I'll probably swap them and get a hopefully quieter running rear diff that way. Right now even after a rebuild, new bearings and a pretty decent pattern on the ring gear, they howl on light cruise......I am pretty sure there is nothing wrong, but the sound drives me nuts!!! (I know, just drop the muffler!!)

    Cheers!
     
  9. nuclearlemon

    nuclearlemon not an addict Moderator

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    no, don't drop the muffler...that just makes you seem like one of those penis boys with the rice rockets and the lawnmower on speed exhausts....instead, just get a set of swampers :D
     
  10. Nick the Carpenter

    Nick the Carpenter

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  11. bad_religion_au

    bad_religion_au

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    maybe it's a semi floating rear axle thing
     
  12. Nick the Carpenter

    Nick the Carpenter

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  13. nuclearlemon

    nuclearlemon not an addict Moderator

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    yep, it's a semi floater thing.
     
  14. bad_religion_au

    bad_religion_au

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    like jeep things, we'll never get it
     
  15. 1Fine40

    1Fine40 Rust Buster SILVER Star

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    Full floaters.....what a nice concept! (an unaffordable one for me, but nice nonetheless!)
     
  16. krzyabncanuck

    krzyabncanuck USFS HOTSHOT

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    You know, if you are running open front and rear or locked front and rear it is a good idea every few years to rotate the diff's anyhow. Share the ware on the gears and such.