I just did a brake job on my dually. I found a lot of gear oil in the hubs and it appeared that the bearings were being lubed by the differential oil. When putting things back together my Chiltons said to re-pack the bearings with high temp bearing grease and dump 1 oz of gear oil into the hub before putting it back on. So I did all this.

It seems that if the bearings are lubed with differential oil that the bearing grease would just get washed out eventually. When I took it all apart, there was no bearing grease in the bearings, just gear oil.

Does this make any sense?