Tractor Repair: 706 International, rear axle shafts, tapered roller bearings

Question
QUESTION: How do you get the oil in the final drives of a 706 International?

ANSWER: Hello,

  You don't need to do anything, the oil will get into the final drives when you fill the transmission and rear end with oil.

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QUESTION: All the hydraulic oils have water in them (yellow, milky oil) except the final drives.  When drained there was only regular oil (no milky) and appeared to have no water.  So how does the final drive get filled by the hydraulic oil reservoir?

Answer
Hello,

  When the transmission and rear end are filled, the oil can run through the tapered roller bearings on the inner ends of the rear axle shafts.  There are no internal seals to keep the compartments separate, and the rear end housing has holes all the way through where the inner axle bearings are.  When the pto housing is removed, you can see the inside of the rear end and you can see the inner ends of the axle shafts and the bearings.  There are no filler plugs on the axle housings, so the oil can only get in from the rear end housing.  Since the holes are at the height of the axle shafts, the oil won't drain out of the final drives when the oil is drained out of the rear end, so they have separate drain plugs.