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Dana 300 Gear Pressure Angle?

Discussion in 'Builds and Fabricators Forum' started by blalp!, Oct 23, 2021.

  1. Oct 23, 2021
    blalp!

    blalp! Member 2021 Sponsor 2020 Sponsor

    Concord, NH
    Joined:
    Aug 16, 2019
    Messages:
    144
    Does anyone know the pressure angle of the gears in the Dana 300? I am hoping to confirm that the input gear of the D300 would be the same cut at the 26 tooth input gear found in D18 cases with the 1-1/8” shaft.

    Why? I have acquired a GM NP435 that has a 30 spline tail shaft. Stubbornly, I would like to make a short custom adapter to mate to a D18. It appears that the D300 input gear is 30 spline with 26 teeth. Any thoughts on making this work would be appreciated.

    -blalp!
     
  2. Oct 23, 2021
    W2SNO

    W2SNO New Member

    Joined:
    Apr 23, 2003
    Messages:
    23
    I assume you are looking for data on the 8131685 ?

    If so, I have not been able to find any, but on my next research trip in a few months I'll add it to the list.
     
  3. Oct 23, 2021
    blalp!

    blalp! Member 2021 Sponsor 2020 Sponsor

    Concord, NH
    Joined:
    Aug 16, 2019
    Messages:
    144
    That looks to be the same/similar to the one I found on eBay. The stamped number on the gear I found was 30081. Certainly any effort you put into this would be greatly appreciated. Thank you!
     
  4. Oct 23, 2021
    W2SNO

    W2SNO New Member

    Joined:
    Apr 23, 2003
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    300081
     
  5. Oct 24, 2021
    jeep peep69

    jeep peep69 Member 2021 Sponsor

    redding ca.
    Joined:
    Dec 8, 2007
    Messages:
    409
    The rear output bearing on the gm 435 is the reason no one makes an adapter to a Dana 18 . Good luck on this
     
    blalp! likes this.
  6. Oct 24, 2021
    blalp!

    blalp! Member 2021 Sponsor 2020 Sponsor

    Concord, NH
    Joined:
    Aug 16, 2019
    Messages:
    144
    The bearing is the same, it’s the bearing retainer that is different. While the Ford and Dodge have the square or trapezoid pattern, the GM has three bolts in the square pattern with one bolt offset. The other common concern with the GM 435 is the input bearing. Some (many?) have roller input bearings. The transmission I acquired has the tapered input bearing. In my case, I could purchase a Novak or AA kit, plug the offset hole, and drill and tap the hole in the correct location. If I can’t work out a custom adapter, I will purchase a kit. I believe the kits are designed so most shade tree mechanics can easily install them. If I am able to come up with a gear that fits the GM main shaft, or modify a Ford/Dodge shaft to fit the factory D18 input gear, then I believe a one inch adapter can be made. Is 1”vs 3.5” worth the effort, maybe. However, I’m willing to risk success and try it.
     
    jeep peep69 likes this.
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