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Strangeness with the Dana44/14BFF I just purchased...

Discussion in 'The Garage' started by BlackDog714, Jan 12, 2004.

  1. BlackDog714

    BlackDog714 1/2 ton status

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    I just purchased a Dana 44/14BFF for $200 and the PO said they were 4.10's. I got them home and spun the drum, only to find that the drum only turns the yoke 2 times per revolution /forums/images/graemlins/thinking.gif

    The Dana 44 did the same thing...

    Is there even such thing as 2.05 gear ratio???

    I havent taken the covers off yet, as it was dark when I got home, but what am I doing wrong?????
     
  2. ZZ4x4

    ZZ4x4 1/2 ton status

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    Thats normal. Just double the number. It's 4.10. If you have a locker and both wheels turn the same way , then you'll count 4.10 revs of the pinion. If you have an open diff, turning a wheel will only show 1/2 the revs.
     
  3. Burt4x4

    Burt4x4 3/4 ton status

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    Take th cover off and look at the ring, you should beable to find the tooth count number that looks like this 41:11, thats is 41 teeth on the ring and 11 on the pinion. If my brain is remembering right that is the number I have on my 4:10s.
    hope this helps
     
  4. Beast388

    Beast388 1/2 ton status

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    [ QUOTE ]
    Take th cover off and look at the ring, you should beable to find the tooth count number that looks like this 41:11, thats is 41 teeth on the ring and 11 on the pinion. If my brain is remembering right that is the number I have on my 4:10s.
    hope this helps

    [/ QUOTE ]

    41 & 11 gets you 3.73's
    41 & 10 gets you 4.10's on the 14BFF
    45 & 11 gets you 4.09's on the D44.

    /forums/images/graemlins/thumb.gif /forums/images/graemlins/thumb.gif /forums/images/graemlins/thumb.gif
     
  5. BlackDog714

    BlackDog714 1/2 ton status

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    [ QUOTE ]
    Thats normal. Just double the number. It's 4.10. If you have a locker and both wheels turn the same way , then you'll count 4.10 revs of the pinion. If you have an open diff, turning a wheel will only show 1/2 the revs.

    [/ QUOTE ]

    I was hoping that was the case, but it makes no since to me... One would think that 1 turn of the drums should turn the yoke 4 times no matter what.
     
  6. Executioner

    Executioner 1/2 ton status

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    No way !
    There is more to it than that.
    Spider gears(Pinion gears) and side gears also have there own ratio.
     
  7. RustBuket

    RustBuket 1/2 ton status

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    Well since the two wheels are turning opposite directions, you have to add up the revolutions I guess.
     
  8. 84_Chevy_K10

    84_Chevy_K10 Banned

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    [ QUOTE ]
    No way !
    There is more to it than that.
    Spider gears(Pinion gears) and side gears also have there own ratio.

    [/ QUOTE ]

    12 bolt fronts are different though right?

    Moron....
     
  9. Confedneck

    Confedneck 3/4 ton status

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    spider gears have their own ratio? wow.. read more, talk less

    the effective gear ratio of ANY conventional differential is determined by dividing the number of ring gear teeth by number of pinion gear teeth..

    that is all, nothing less nothing more..
     
  10. ben427

    ben427 1/2 ton status

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    What he means is that if you hold one wheel and spin the yoke, the free tire will spin twice as fast as the pair would if spun at the same time. This is due to the spider and side gears. Jack up your truck if its an open diff and take a look.
     
  11. BlackDog714

    BlackDog714 1/2 ton status

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    I will count the next time it's light out and I have a day off, but beyond that, does my issue sound odd? It "feels" odd to me /forums/images/graemlins/confused.gif
     
  12. Confedneck

    Confedneck 3/4 ton status

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    pull the covers.. its the most exact way to tell your ratio..
     
  13. Executioner

    Executioner 1/2 ton status

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    Yes, and No ! It depends on you....
     
  14. 6.2Blazer

    6.2Blazer 1/2 ton status

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    As stated, in an open diff if you just spin one tire while the opposite side remains stationary, you have to multiply the number by 2 when determining the gear ratio.

    The reason for this is that when you spin one tire while the other is stationary, it spins the axleshaft, which spins the side gear, and then the spider gear......before actually causing the carrier and ring gear to spin. It's kinda' like a planetary gear setup.

    I see this all of the time while watching trucks with a locker in the rear and an open front axle. When spinning in mud the one tire spinning on the front will be spinning a lot faster than the two rear tires.

    Theoretically the gear reduction will be cut in half to the one spinning tire on an open diff vehicle. However, you would never notice this change because while doing a "one wheel peel" there is zero torque being transfered to the spinning tire....and zero times any gear reduction is still zero.
     

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