I recently disassembled my front brakes. When taking the hub/rotor off I found that there was not very much grease on the bearings. Even though the bearings weren't giving me any problems, I'm replacing the rotors and bearings because the rotors have become worn. My question is if anybody has ever repacked their bearings and filled the cavity between the bearings with grease so that the bearings won't run dry.

I try to wipe out the old grease with a couple paper towels. Primarily you need to make sure the bearing gets really greased.

Since you didn't ask....

It's an art to "pack" the bearing by hand. I blob some grease on my palm (use gloves) and scrap the edge of the bearing into it, this forces grease in the space between the inner and outer bearing surfaces.

Do both sides, rotate the inner bearing by hand and repeat. You should start seeing grease coming out of the bearing on the rollers.

Or....go buy a bearing packer for 10.00 and then you are sure you got a good "pack". It also allows you to pack 2 at a time and do it without the big mess in your hands (that just doesn't sound right).

Do us professionals a favor and do not pack the hub with grease...it's a PITA to clean up later. one small ball of grease in the hub is plenty.

Don't fill the hub with grease. The hub heats up with repeated stopping and the grease helps hold the heat. The hub/rotor will cool down faster between stops if it's not packed full of grease. Get it hot enough and all the grease turns to liquid and runs out of the bearings.

I've never heard of any reason to have grease in the hub, period. The bearings need the grease, not the spindle or hub. There will be enough grease on the outer surface of the inner bearing race from handling it to lube it for installation and prevent freezing. And wiping the old grease off the spindle with rags of paper sill provide enough protectin against rust on that surface. So any additional grease is just a PITA and a potential mess when or if it melts. I always hated it when someone put extra grease in the hub. Made me want to charge more for the mess.

This is the easiest wheel bearing packer tool that I have ever used.

http://buy1.snapon.com/catalog/OBJECTS/44400/44322.JPG

The Snap-On number is YA470B and it is $38. I is a very good investment. Very clean and easy to use.

I have a couple of different types. One like the one above. I don't think it's worth the plastic it's made of. I have one that's 2 cones with a threaded stud in the middle. It's got a grease fitting in the top of the stud. It works well and you can get it at any parts store for about $12.
Just to throw my $.02 in