Mike, is this Dana/ Spicer axle of G.M. corp. G.M. used c locks to hold axles in Dana has brg pressed onto axle, flange w 4 bolts hold axle in. In short, Dana has sealed axle bearing. On G.M. axles I line to fill it the jack each side up one at a time to get oil down the tube & out to the bearing, then recheck fluid level with it flat.