Step two: remove and clean/replace the bearings
Remove the bearings for inspection and cleaning, placing the bearings in a box or tray. Greater access can be gained by prising off the dust covers with a small, flat-bladed screwdriver or pick, but Jon’s advice is to leave them in place, unless you are an experienced mechanic and can judge the required force to remove them without damaging the seal.
We’ve used a rear hub for this example, and the bearings shown are ¼”. Front hub bearings in cup and cone systems typically are 3/16”. Typically, nine are used either side. This configuration leaves space for movement of the bearings, which, to the untrained eye, can look like space for a tenth bearing.
Ball bearings are low cost items. Jon recommends replacing them as a matter of course. Different grades are available, however, and those supplied with more expensive hubs tend to be of higher quality and therefore more expensive to replace. Should you choose to retain the bearings, place them on a clean rag, fold the rag over the bearing so they are covered, and agitate to clean.