The rear is lubricated with rear-axle oil, so no need to pack it. Just be sure your rear axle isn't low on oil. The front hubs will do fine with any good-quality wheel-bearing grease; I used Castrol, recently, just because it seemed right. So far, no leakage, heating, or similar problems. Mobil 1 is very good stuff too. Just work it in well, use plenty but don't go nuts, and it should be fine.