Mercruiser Non Greasable Gimbal Bearing | Sierra 18-21006 Sierra 18-21006 Gimbal Bearing Mercruiser Non Greasable Gimbal Bearing Fits Mercruiser Gen II drives from 1998-2010 Fits Mercruiser Bravo I/II/III and X/XR/XZ drives from 1996-2010 Replaces Mercruiser 30-879194A01