Front wheel bearings on U.S.-built passenger cars and light-duty trucks are generally a set of tapered roller bearings that are mounted in opposing directions to accommodate various loading combinations on various vehicles. Always replace bearings in kind and according to manufacturer's specifications.
Not all manufacturers recommend identical adjustment procedures and specifications, but following is one general set of rules that can be followed on most vehicles, if specific instructions and specifications are not available:
While rotating wheel and tire assembly, tighten wheel bearing adjusting nut to approximately 12 ft. Ibs. to seat all bearing parts.
Back off adjusting nut approximately one "flat" and re-tighten nut until it is finger tight.
Install cotter pin. If cotter pin holes do not line up easily, back off on nut for alignment. Never tighten adjusting nut to line up cotter pin holes.
Modern tapered roller front wheel bearings must never be pre-loaded (adjusting nut and washer exerting tension on bearing assembly when wheel and tire are raised off the floor). Bearing adjustment is correct when the wheel assembly can be manually moved in and out a minimum of .001" and a maximum of .005" (representative specification).