Jacking the trailer

• 1). Move the trailer to firm, level ground. If you attached the trailer to your vehicle to move it, unhook the trailer.
  
  
• 2). Put chalks in place to prevent the trailer from rolling. You can use cinder blocks or wood as chalks. Place a chalk behind a wheel on each side of the trailer.
  
  
• 3). Loosen the lug nuts on the tire. Use your lug wrench to rotate them counterclockwise until you can loosen them by hand.
  
  
• 4). Jack the trailer up. Place the jack under the frame or axle of the trailer. Crank the trailer up on the jack. Jacks vary on how you do this; you crank the handle on some and move the handle up and down on others.
  
  
• 5). Take the lug nuts all the way off by hand.
  
  
• 6). Remove the wheel.
  
  

Remove Dust Cap and Hub and Inspect Bearings

• 1). Use a flat-head screwdriver and hammer to gently pry the dust cap off. The dust cap is the cap on the outside portion of the wheel hub.
  
  
• 2). Take the cotter key out. Use your pliers to bend the ends of the cotter key back so that they are straight. Grab the cotter key from the opposite end with your pliers and pull it out. Spin the bolt holding the hub in place counterclockwise until you can remove it. Now, you can pull the hub off of the axle stub with your hands.
  
  
• 3). Slide out the outer bearing from inside the hub by reaching your fingers into the hub and pulling it out.
  
  
• 4). Pour a degreasing agent into a bowl or some sort of tub that your bearings will fit into. Put your bearings in the bowl. You can find degreasing agents at an auto store or use petroleum-based products such as gasoline as well.
  
  
• 5). Inspect the bearing. Take the bearing out of the bowl and wipe it off with a soft cloth. Spin the bearing around in your hand as you feel for any resistance, roughness or other obvious wear and tear.
  
  

Packing the bearings

• 1). Get your grease gun ready. You prepare most grease guns by pulling the end back to prepare it for the tube of grease. Then place the tube of grease in the gun and put the cap back on.
  
  
• 2). Put the bearing in the bearing packer. The packer is two shallow cones. Place the bearing on the top of the bottom cone and screw the top cone onto the bottom cone with the bearing in between.
  
  
• 3). Attach the top end of the bearing packer to the end of the grease gun. Pull the grease gun trigger to pump grease into the bearing packer until you see grease coming out the sides of the bearing.
  
  
• 4). Take apart the bearing packer. Unscrew the top from the bottom and take the bearing out.
  
  
• 5). Apply grease to the outside of the bearing with your hands. The grease packer applied grease to the inside.
  
  

Putting it back together

• 1). Put the bearing back in the hub the same way you took it out. The tapered end of the bearing should face into the hub.
  
  
• 2). Slide the hub back onto the axle. Place a quarter-size amount of grease into the inner part of the hub. Spin the bolt back onto the axle to hold the hub in place. Place the cotter key through the axle stub to lock the bolt in place. Open the ends of the cotter key so it cannot come out of the axle.
  
  
• 3). Place a quarter-size amount of grease on the inside of the dust cap. Put the dust cap back on the hub and gently tap it into place with a hammer.
  
  
• 4). Place the tire back on the hub and tighten the lug nuts by hand.
  
  
• 5). Take the trailer off the jack. Use the lug wrench to further tighten the lug nuts.