Servicing your trailer’s wheel bearings is one of those periodic maintenance chores that should not be neglected. Properly maintained and lubricated wheel bearings can help keep you from being stuck on the side of the road when you’d rather be on your way to the fun
How it’s Done
The job may be a little messy (you have to manually apply the grease to the bearings) but can be done by most intrepid do-it-yourselfers. Here are the basic steps:
1. Park the trailer on level ground, lowering the tongue jack and chocking the wheel opposite from the one you’re working on. Loosen lug nuts before jacking the trailer up and placing safety support under the axle.
2. With the trailer jacked up and supported, remove the lug nuts and wheel.
3. Carefully pry the dust cap off the hub with a screwdriver. Wipe away grease and dirt on the inside and outside of the dust cap.
4. Use needlenose pliers to remove the cotter pin from the spindle nut, then remove the nut and washer. Discard the old cotter pin; you’ll replace it with a new one (available from auto parts or hardware stores).
5. Remove the hub from the spindle carefully, since one set of bearings will come out with the hub.
6. Use a small block of wood and a hammer to loosen the seal holding the rear bearings in place. Always replace this seal with a new one (available at auto parts or hardware stores).
7. Clean the old grease from the bearings and races (the “doughnut” rings that hold the bearings in place inside the hub) with a small brush and a solvent such as kerosene in a small pan.
8. Inspect all bearings and races for rust, corrosion, wear or pitting as you clean them. Replace any that are damaged.
9. While bearings and races dry, clean the spindle and the inside of the hub with a rag. Spray-on brake cleaner will clean these up nicely.
10. To repack, use the grease recommended by the axle manufacturer (see your owner’s manual). Using the wrong type or grade of grease will cause the bearings to fail due to heat breakdown. Take some grease into your hand and work it into the bearings, starting on the wider side. Fill the cage and rollers with grease, and coat the inside of the hub with grease as well.
11. Put the back bearings and races in place inside the hub, then use the wood block and hammer to install the new seal. Now place the front bearings and races back inside the hub.
12. With the newly lubricated bearings re-installed, place the hub back on the spindle. Thread the spindle nut back on and tighten, then back it off about an eighth of a turn before installing a new cotter pin. Tap the dust cap back into place.
13. Give the hub a spin to make sure it is turning freely, then re-install the tire and wheel. Tighten lug nuts to the manufacturer’s recommended torque (see owner’s manual).
14. Use the same steps to service the bearings on the opposite end of the axle, making sure that the trailer is safely supported and chocked. If your trailer has tandem wheels, do all the bearings on one side before moving to the other side, being careful to not mix up the bearings and races—the bearings must go back into the same hub and races and the hub must go back onto the same spindle.
Tip: While you have the tire and wheel off, check the trailer brake components, suspension and tire for damage or wear. It’s an ideal time to replace the brake shoes or magnet, or to have the drum turned if it’s worn. Top up the air pressure in the tire to the recommended level while you’re at it. Check springs and suspension for damage, missing bolts or other potential problems.
Wheel bearing service is generally recommended at least once per year; check your owner’s manual for the manufacturer’s recommended service intervals.
Read More RV Tips Read More Tech Tips