Differential/Lube general question

Discussion in 'Volvo Forum' started by MIg25, Apr 18, 2024.

  1. MIg25

    MIg25 Light Load Member

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    Hello
    General dumb question, I think I know the answer but I just want to confirm with the experts.
    Volvo VNL and most 6x4 trucks the rear differential is the one tractioning all the time, is that correct?
    Which oil are most popular out there for the differentials?
    I found Sinopec for $109 per bucket.

    Gear oil.jpg
     
  2. Big Road Skateboard

    Big Road Skateboard Road Train Member

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    For manual trans, diffs, trailer and steer hubs, I've used synthetic 75-90 for over 20 years.
     
  3. Goodysnap

    Goodysnap Road Train Member

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    You should re think putting gear oil in any manual trans. This is not the approved fluid for transmissions.
     
  4. Big Road Skateboard

    Big Road Skateboard Road Train Member

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    Thanks for the info, but I'll just have to wait for you to tell me why I shouldn't put the same Synthetic 75/90 in it. I'm not gonna waste time looking for a reason.

    If you want to explain, tell me also what difference it will make over the life of the transmission.
     
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  5. Last Call

    Last Call Road Train Member

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    If that’s true then why every time I install a rebuilt manual transmission from Inland it has a tag on it recommending to use synthetic GL 5 ?
     
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  6. Big Road Skateboard

    Big Road Skateboard Road Train Member

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    Eff it, I lied and looked.

    I've used this Castrol 75 90 forever. It's in the new Fuller 18speed in my truck right now, and the same oil I used in all of my customers equipment for years.

    Can't remember about Weller, but for the full 5yr warranty on new Eaton trans, you have to also purchase an approved oil and clutch, or just an approved oil for diffs.

    Every trans I bought included a 5gal bucket of this oil, and usually an Eaton Easy Pedal

    Screenshot_20240418_183828_Drive.jpg
     
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  7. Big Road Skateboard

    Big Road Skateboard Road Train Member

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  8. lester

    lester Midwest's #1 Feed Hauler

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    pretty sure I've always been sold 50w oil for transmission.

    And on a normal 6x4 configuration there isn't one axle that drives all the time. torque goes equal to all 4 wheels until one looses traction. any of the 4 wheels can spin. the one with the least traction front or rear will spin.
     
  9. Goodysnap

    Goodysnap Road Train Member

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  10. AModelCat

    AModelCat Road Train Member

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    Both axles on a tandem are always putting roughly equal power down to the wheels.
     
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