Will 30 spline ring and pinion gears work with 28 spline axles?

Discussion in 'Differential & Driveline' started by 84 Shorty, May 14, 2018.

  1. 84 Shorty

    84 Shorty Full Access Member

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    Im wanting to change my gears from 4.10 to a 3.42 or 3.73. All the ring and pinion gears I am seeing are 30 spline. More than likely my axles are 28 spline since they went to a 30 spline on the 88 years. I have an open rear end, so will 30 spline ring and pinion work? I think I said spline enough in this post
     
  2. bucket

    bucket Super Moderator Staff Member

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    The ring and pinion don't care if it's a 28 or 30 spline carrier.
     
  3. 84 Shorty

    84 Shorty Full Access Member

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    That’s what I figured, thanks for clarifying.
     
  4. crazy4offroad

    crazy4offroad Service Bullshit Filter Soon

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    8.5 and 8.6 are the same, just make sure the gear set you buy matches the carrier break of your current differential.
     
  5. 84 Shorty

    84 Shorty Full Access Member

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    4.10s use the same carrier as 3.73 and 3.42 gears I believe
     
  6. crazy4offroad

    crazy4offroad Service Bullshit Filter Soon

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    A reputable vendor will make it clear what carrier their gears are made for. Depending on the axle 4.10 and up are considered "thick" gear sets designed for 3-series carriers.
     
  7. 436'd skylark

    436'd skylark Member

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    The pinion gear has on an 8.5" rear is 30 spline. That might be what's throwing you off. Lots of sites list that spec as well
     

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