Pinion depth

Discussion in 'Transmission & Driveline Topics' started by TX79Z28, Dec 30, 2017.

  1. TX79Z28

    TX79Z28 Veteran Member Lifetime Gold Member

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    I'm rebuilding the differential in my 79. Im using the old gears and carrier just replacing bearings. If I use the same pinion gear, spacer in the same housing do I need to set pinion depth? I got a pinion depth gauge from Jeggs but the instructions suck ass!
     
  2. big gear head

    big gear head Veteran Member

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    Jul 30, 2001
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    If you do a pattern check on the gears before you take anything out then you will know what the pattern needs to look like. You also need to check the backlash before removing anything. If you have already disassembled the rear end without doing this then you have no idea what shims you need to use when putting it back together and you won't know if you got it right or not.

    If you check the pattern then you need to take pictures of it so that you can refer to them when you put it back together. If you use the original pinion shim and set the backlash to what it was before and the pattern looks the same then great. If it doesn't look the same then you will probably need to make adjustments.
     
  3. TX79Z28

    TX79Z28 Veteran Member Lifetime Gold Member

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    Didn’t take pinion gear out yet but I know which shim was on what side of the carrier
     
  4. Knuckle Dragger

    Knuckle Dragger Administrator Staff Member Lifetime Gold Member

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    Waddell AZ
    Big Gear Head has far more experience then I do, that said I've only had to "re-shim" one rear end when I changed bearings. The other 30-40 times everything was right with the old shims. Since it's already apart I'd put it back together with the old shims and new bearings, check the pattern and backlash, adjust from there.
     
  5. TX79Z28

    TX79Z28 Veteran Member Lifetime Gold Member

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    Thank you both. That’s the plan , going to order the rebuild kit next week
     
  6. Knuckle Dragger

    Knuckle Dragger Administrator Staff Member Lifetime Gold Member

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    IMO spend the money on Timken or Koyo bearings and if you buy shims get the interlocking shim kit. It's much easier to use.
     
  7. TX79Z28

    TX79Z28 Veteran Member Lifetime Gold Member

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    May 3, 2007
    San Antonio, TX
    If I am using the same carrier, housing, and gears shouldn’t putting the original shims in the same position work?
     
  8. camaro71/holland

    camaro71/holland Veteran Member

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    Side note: have you marked the carrier caps before disassembly?
     
  9. TX79Z28

    TX79Z28 Veteran Member Lifetime Gold Member

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    San Antonio, TX
    I did. I kept right and left separate as well as their orientation
     
  10. camaro71/holland

    camaro71/holland Veteran Member

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