Bearings are what allow the gears to rotate smoothly. They are generally designed from bronze or brass, and they match into races (or grooves) while in the gearbox housing. Contaminants can enter your gearbox oil via vents or even the fill tube during checking/filling. Most of the time, nevertheless, contaminants https://filtergearbox83703.tinyblogging.com/an-unbiased-view-of-filter-gearbox-77761626