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  1. #1

    Default Differential Gear Swap Pattern Check

    Just curious to see if anyone knows if this is an acceptable pattern.

    Let me know.
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  2. #2


    Looks like the pinion isn't quite deep enough. What's your backlash spec? .015" sounds like a lot.
    When you hear hoofbeats, look for horses not zebras.

  3. #3


    This is my base set up. I'm going from here, i will try to reduce the shim on the main bearing. Once i get pinion depth i'll go after backlash, i do not know what the spec is suppose to be on the gears, i cannot find it anywhere in the book they supplied. My gears are USA Gear, in a green box.

  4. #4
    Sr. Apprentice LURCH's Avatar
    Join Date
    Aug 2011
    North East Tn.


    I was thinking .007/.009 and I agree on the pinion depth.

  5. #5


    You need MORE shim under the inner pinion bearing. That will push it towards the center of the ring gear.

  6. #6


    Here's what i got now, 0.007 backlash.

    And the pattern seems more rounded and centered. I can say I'm happy with this pattern. Does seem like the pinions too far out on the drive side though.... Coast side is perfect.

  7. #7


    I got ambitious and changed the pinion depth...

    Let me know what you think, tomorrow i'm sealing it all up.

  8. #8
    TRPLXL2's Avatar
    Join Date
    Jan 2009
    Norwalk, Ohio
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    Very interesting post here, I learned something new today! My dad is very old school as he used to take a piece of newspaper and roll it through the gears, he would make his adjustments based on how the paper came out....

  9. #9


    Looks good to me. Just curious, did you use a setup bearing for the inner pinion?

  10. #10


    I re-did it again and got basically the same pattern with 0.005"-0.006" backlash, so i'm going to stick with that.

    I took a brand new bearing and bored out the inside so that it could slip on and off. The bearings from my rebuild kit from stock differ in size and angle. So i couldnt use the stock bearing for set up. Had to buy a whole new bearing. Well worth the $30.

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