If you know what you are doing the bearings can be removed without damaging the retainer. But like john said. it is the inner seal that is leaking and causing the problem. There should be no lubricant getting to the outer seal to leak unless the inner seal is leaking. The axle bearings are packed (much like the front wheel bearings) and are not lubricated with lubricant from teh rear end. if rear end lube gets into them it washes the grease out of the bearing and then leaks into the brake drum and creats grabby brakes and a mess.