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Cat 966 oil

Discussion in 'Lubrication' started by alaskaforby4, Mar 2, 2017.

  1. alaskaforby4

    alaskaforby4 Senior Member

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    Owner Operator
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    Alaska
    IMG_0431.JPG Hello, I am looking to change the differential oil in a 76J 966C Cat Loader the book reference is 90w oil. However, i am finding this hard to find. Have the oil recommendations changed since then or do I need to find this specific oil. Thanks
     
  2. Nige

    Nige Senior Member

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    G..G..G..Granville.........!! Fetch your cloth.
    You're correct, specs have changed over the years and Cat have gone away from EP oils in diffs & final drives.
    Use an SAE50 TO-4. It will work fine. Because the two types of oil are classified differently the viscosity of an SAE50 TO-4 is actually pretty much the same as an SAE90 EP oil.
     
  3. kshansen

    kshansen Senior Member

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    Retired Mechanic in Stone Quarry
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    What I find strange is the listing for brake fluid down at the bottom of the page. Been a few years since I actively worked on a 76J Cat but every one we had had straight air brakes, not air over hydraulics. Then again this might be a "generic" type fluids chart and not one specific to the 966C family.
     
  4. alaskaforby4

    alaskaforby4 Senior Member

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    Occupation:
    Owner Operator
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    Alaska
    Perfect thanks guys!
     
  5. DB2

    DB2 Senior Member

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    Jan 4, 2015
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    Winnipeg MB Canada
    It's been a while but I think the 966 shared an operators manual with both a 950 and a 980 so somewhat generic.