When adjusting bearings on a trailer, or any vehicle, the bearings should be packed well first. There should be a grease seal on the inside the hub that seals against the spindle. When the bearings are correctly adjusted and have a thread lock installed, they should not need to be readjusted until the bearings are removed for repacking. Wheel bearings should never be installed too tightly or they will promptly heat up, score the bearing races and ultimately fail.
Raise and support the side of the trailer on a jack stand. Remove the tire with the lug wrench. Remove the grease cap using the screwdriver and hammer to tap it off. Remove the cotter pin with the wire cutters.
Remove the axle nut using the adjustable wrench. Pull the hub off and turn it on end. Remove the rear seal using the screwdriver to pry the seal out and remove the bearing. Hand grease both the outer and inner bearing.
Install the rear bearing and tap the rear seal in place with the hammer. Install the hub on the spindle and install the front bearing followed by the washer and the axle nut.
Adjust the bearings by using the adjustable wrench to tighten the axle nut. Tighten the axle nut loosely until there is no in-and-out play in the hub. Once this is accomplished, tighten the nut ½ turn and then back the nut off ¼ turn. Check the hub for any play up and down and side to side. If any play is felt, tighten the nut ½ turn and recheck.
Install the cotter pin followed by the grease cap.
