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4:11?

Discussion in '40- & 55-Series Tech' started by Mrpoopypants, Mar 8, 2004.

  1. Mrpoopypants

    Mrpoopypants Guest

    What is the stock gearing in a 78 FJ-40?
    4:11 is what comes to mind.
    If they differ, how can i tell what mine are?

    Thnx
     
  2. Cruisergreg

    Cruisergreg

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    That year might 3.70.
     
  3. Poser

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

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    Pull the rear cover, and count the teeth...that would remove all doubt.

    If this truck has not been messed with by a previous owner..I know, ha ha ha, but this *should* have the much saught after and coveted fine-spline 4.11 gear set, as in the USA, depending on the month of production, the 3.73 ratio was not in the 40 series until the 79 modle year, which could have started in 08/78...

    There is a tag on the passenger side bulkhead that has an axle/gear ratio code..
    Should have a 'K08' which would be 4.11, or a 'K05' which would be a 3.70...

    But I still think that removing the cover is the best way to verify a gear ratio...

    Good luck!

    -Steve
     
  4. s79bj40

    s79bj40

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    why did america get covers on the diffs and we didn't? I have never even seen a cruiser with a removable cover, they are all welded closed and if you want to count the teeth you need to remove the carrier. It would have been nice to have a look see inside.

    sam
     
  5. Toyoland66

    Toyoland66

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    You are acting like you all got screwed by not having removable diff covers......

    The reason your are welded up is because they are full floaters, US landcruisers got semi floaters in the rear and the cover needs to be removable to get the C clips.

    I'll trade if you want.......
     
  6. s79bj40

    s79bj40

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    must just be cheaper welding the back on, just be thankfull you dont have a landrover, mine has semi-floaters and there is no access cover.
     
  7. Poser

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

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    9" Fords, and there are other axles out there that are the same way...

    Really not that big of a deal...

    Good luck!

    -Steve
     
  8. Mrpoopypants

    Mrpoopypants Guest

    OK, I checked the plate on the fire wall:
    Trans/Axle = H42 K082 :D

    Plate on the door frame:
    Nov 1978 :-\

    And I do have a removable cover on the rear.

    A-B+C=4:11? :beer:
     
  9. woody

    woody unhelpful spotter Staff Member Admin

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    I know of someone who ground off their front welded diff cover, drilled and tapped it for a rear bolted cover, and did it that way...neat idea.

    Mort, you need to count driveshaft rotations. Put the rear axle on jackstands, put the t-case in neutral, and rotate the driveshaft by hand. if it takes more than 4 revolutions to spin the tire one rotation, it's 4.11. Less means it's 3.73.
     
  10. incogrhino

    incogrhino

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    My 12/78 fj40 has the 4:11
     
  11. FJ40-GARAGE

    FJ40-GARAGE I`ll be back....

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    My 4/1977
    has 3.70 and Drumbrakes on the Frontaxle..............

    Okay......... it was bought in Germany .......... :D made for the Autobahn.

    With the Original Tires that was easily good for a 100 m/pH .
     
  12. yooper

    yooper SILVER Star

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    It's not 4:11, it's 4.11:1

    The : indicates a ratio, so 4:11 means "a ratio of 4 to 11", when in fact we mean "a ratio of 4.11 to 1"

    This is trivial nomenclature, but I'm a trivial kind of guy.
     
  13. cpip

    cpip

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    What are the higher gear ratios (lower numerically) that could be swapped into a '69? I am looking at a diesel swap and need to lower rpm's and raise road speed.
    Are new gears a possibility?
     
  14. bad_religion_au

    bad_religion_au

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    the 3.70:1's should bolt in should they not???