On anything built since probably in the 70's, use the gear oil out of the pumpkin to lube the bearings in the wheel hubs. There are a few exceptions that I have seen, but those were on old trucks. On some of the old trucks they had a grease seal that went on the wheel hub before you slid the axle shaft in the housing that would keep the gear oil from getting in the hub, and keep the grease in the hub.