How to Assemble a Trailer Wheel Hub
- 1). Clean the inner and outer wheel bearing assemblies, the axle shaft and the wheel hub in solvent before assembly. Use a parts brush to loosen large deposits of dirt and grease. Rinse the parts thoroughly in solvent and let them air-dry.
- 2). Pack the inner and outer wheel bearing assemblies with axle grease as follows: Place a blob of axle grease onto the palm of your hand. Hold the outer wheel bearing with your other hand and force grease into all nooks and crannies in the bearing by pushing the edge of the bearing into the grease on your palm. Continue around the circumference of the bearing until it has been completely packed with grease. Repeat this step for the inner wheel bearing.
- 3). Apply a layer of axle grease to the trailer axle shaft. Push the inner wheel bearing (the larger of the two bearing assemblies) onto the axle shaft with the thicker end of the bearing facing inwards.
- 4). Push the wheel hub onto the axle shaft until it makes contact with the inner bearing. Hold the hub in position with one hand and push the inner bearing onto the axle shaft (with the thinner end facing inwards) until it makes contact with the wheel hub.
- 5). Hold the assembly in position with one hand and push the axle washer onto the axle shaft with the other, being careful to line up the slot in the washer with the notch in the axle shaft. Run the axle nut onto the threaded end of the axle shaft with an adjustable wrench in a clockwise direction. Place a torque wrench on the axle nut and make sure it is tightened to the foot-pound value recommended by the trailer manufacturer.
- 6). Place a new cotter pin through the hole on the axle nut so that it protrudes through the axle shaft and the other side of the nut. Bend the protruding end of the cotter pin with a pair of pliers to make sure it does not back out.
- 7). Push the dust cap onto the axle shaft and tap it in lightly with a rubber mallet until it seats into position.
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