Tech information furnished by Jude Donato
The following are scans of the original ~1973 manual for the early upright-style Warn M8000 and M6000 winches...applicable model numbers include: Warn 5687, Belleview M6000, Warn M8000, Warn 5721, and Warn 7200.
Bearing information follow the scanned images...click each images for a fullsize/new window.
Bearings (except plastic bearing) sourced from Applied Industrial Technologies, Roanoke VA.
Any local bearing distributor (Pacific Bearing) will be able to source the bearings or cross reference the bearing actual part numbers.
Grainger and McMaster-Carr can cross reference
Inspect bearings for condition, if OK they do not have to be replaced.
NOTE: the Warn 5687 does not have a drain plug for the gearcase! Drill and tap the bottom of gearcase inbetween the two main housing bosses for a 1/8-27 NPT drain plug.