How hard are differential seals to do yourself on a Freighliner?

Discussion in 'Ask An Owner Operator' started by MTMAUS, Oct 26, 2025.

  1. KDHCryo

    KDHCryo Medium Load Member

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    I was just adding Permatex the crud out of those out differential gaskets while you have it apart.

    I love that permatex aviation gasket sealer.
     
  2. Star Rider

    Star Rider Road Train Member

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    Make sure the rear end vent isn't plugged up or you will be doing it a 3rd time.
     
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  3. Brandonpdx

    Brandonpdx Road Train Member

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    that and make sure the driveline is running in balance. If it was just done a year ago and leaking again, something is likely up that’s causing the seal to leak, because those usually last a hell of a lot longer than that if everything is running right.
     
    Last edited: Oct 29, 2025
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  4. Brandonpdx

    Brandonpdx Road Train Member

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    Drivelines slightly out of balance can also cause headaches like this. It will tell on it somewhere.
     
  5. Brandonpdx

    Brandonpdx Road Train Member

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    Ford makes some bad ### stuff too. The grey stuff they use to seal the pan on a 7.3 engine.
     
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  6. MTMAUS

    MTMAUS Light Load Member

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    What's the best way to ensure that it's all running in balance? Check ride height? Check everything is squared?
     
  7. Diesel Dave

    Diesel Dave Last Few of the OUTLAWS

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    Replace the yoke. There not that expensive. And install with new seal. I kept replacing seal. Finally replaced the yoke and never leak again. The speedy seal kit didn’t last either. And never used the same locking nut. Buy new.
     
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  8. KDHCryo

    KDHCryo Medium Load Member

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    Pull the driveshafts and send 'em to a balance shop.

    I guess you could jack up the whole rear end and spin it to about 25MPH on jacks and rig a runout gauge on the driveline, just make sure insurance is up to date, including life...