In order to safely drive your trailer, it is important to make sure all the components are working and to replace them if they are not. In particular, a worn or damaged trailer hub can ruin your trip before your boat even hits the water. Make sure to check your hubs before you leave, and purchase replacement parts if necessary at a trailer retailer such as Champion Trailers.
Exposing the Trailer Hub
Make sure you have the following tools before dismantling your hub: flathead screwdriver, mallet, 1” wooden dowel, heavy-duty degreaser or low suds dish detergent, hollow cinder block or several 2x4s, and a roll of paper towels. You may also need a chisel. When inspecting your hub first remove the tire itself from the trailer. Once the hub is exposed, you will need to remove the grease cap. Use your flathead screwdriver and pry the cap off in a circular motion.
Removing the grease cap will reveal the castle nut. This is what holds the trailer hub and bearings in place. It will be connected to the spindle by one of three devices. Usually you will find a cotter pin which you can simply bend and pull out. You may find a “tab” on the castle nut. This is the tang washer. Use your screwdriver to push the tab back towards the spindle. If the spindle is D-shaped you have an EZ lube spindle, in which case it will almost certainly have a tang washer. Gently pry off the cage by using a circular motion with your screwdriver.
Removing the Trailer Hub
You are finally ready to remove the hub itself. A trailer hub that is in good condition should slide right off the spindle. Make sure to hold in the outer bearing with a paper towel when you remove it. If it is difficult to remove, rock the hub in a circular motion or use a mallet to tap the back of the hub in a few places. During the colder months you may find the hub froze to the spindle. Use a little more force to knock it loose. The bearing and seal may stay attached to the spindle. Use a chisel to break it loose, but be careful not to damage the spindle. The bearings and seal are easily damaged.
Disassembling the Trailer Hub
Now that the hub is no longer attached to the spindle, it is time to take it apart and inspect its parts. First remove the outer bearing and spindle washer. It is closest to the outside of the hub and may have even fallen off when you removed the hub from the spindle. Next, place the hub with the wheel studs up on the cinder block or 2x4s. Insert the dowel rod into the center of the hub and knock out the inner bearing with the mallet. The rod will protect the bearing and race from nicks. The grease seal will be pushed out when the bearing is removed.
Find your bearings and check for nicks, dents, lines, spots, or discoloration in the metal. Any of these issues calls for getting replacements. Check the sides or ends to find the stamped number you will need to purchase replacements. If they are not damaged, clean them with degreaser or detergent and a paper towel and allow them to dry. Because the seal was removed from the hub it will need to be replaced. If the seal does not sit well in the hub or is no longer round it will not work correctly. Find the numbers stamped on the rubber part of the seal to order your replacement.
Next check the race. Check the surface and look for nicks and discoloration. Run your fingernail over it to find any indentations. Generally, if you replace the bearings you should also replace the races. You can find the identification number stamped on one end. In the center of the hub you can see the race sticking out. Work in a circular motion from the inside out and knock out the race with your screwdriver and mallet. This will probably take some time; however, if it comes out after a few whacks you will probably need to replace the hub too.
Make sure to clean out the hub before you begin reassembly. The cleaner it is, the easier it will be. Check your spindle too for any damage. Use the fingernail test and pay special attention to where the seal rides against it. Now that you have checked the condition of your trailer hub and its components you are ready to reassemble and hit the waves!