[ssgharkness020147]

As Travis stated, Mobil 1 being a synthetic will cause more leaks not less. Using a friction modifier in them will really not do or help anything, and will definitely not help any leaks in your hubs. The friction modifier is added to prolong the life of organic materials in your diffs, its use is not called for in geared hubs. The proper hub oil to use is the Lucas Hub oil, if you would like I'll take a picture of a bottle of it for you. It may take some time to swell a seal back up, and stop the leak. If its leaking that badly I highly recommend that you fix the seal rather then trying a quick fix.