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Not necessarily - to my knowledge. I would think that there isn't any 'suction' coming from the diff.


There is a common theory that hot gear oil and the air in the diff from the spinning gears will become instantly cooled upon the housing's contact with cold water. The cooling will cause the air and gear oil to contract and air gets sucked in. That is why the diffs aren't completely sealed to begin with.

Harry Wagner
Harry Situations
4x4Wire's Toyota Section