Greasing sealed bearings?

[Tropic-al]

Has anyone tried to add grease to the sealed bearings with a needle that has the end like a grease fitting meant to be used with a grease gun.
The bearings look and feel/spin fine. They have been there for about 20 years and have only seen 27,000 miles.

[motoman]

Actually haven't.........but one of the two piece spin together cones works great. Grease will force its way past the seal and pack the bearing with no damage or distortion to seal.

[natemoen]

Which bearings? Most likely though the old grease in them has dried up and turned sludgy. May not feel like it but it is. The needle method will not allow the old crappy grease to come out as you try putting new stuff in. Real way to do it is to remove the bearing, POP the seals off and clean.out the old grease and then release.them.

If you are talking about the front wheel bearing and the right rear, the bearings are only about 3 bucks a piece.