There are two seals on the rear axle assembly (really three if you count the big O-ring. Which one are you asking about. The one in the housing or the one on the axle?
If it is the one on the axle here is a write up about changing it and how to get to it.

http://www.4x4wire.com/toyota/maintenance/rear_axle/wheel_bearing/

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Repack your bearings

Most people do not even know that there is a way to repack the "sealed" rear axle bearing!!!!!

Last edited by OOP'S; 05/26/05 04:14 AM.