How to Repack Trailer Wheel Bearings β Step-by-Step Procedure
Every 12 months or 12,000 miles per Dexter's official service manual. Remove the hub, clean and inspect the bearings, pack with fresh NLGI #2 grease by hand, reinstall with a new seal and new cotter pin. Castle nut procedure: torque to 50 ft-lbs while spinning the hub, back off completely, then finger-tight, then back off to the first cotter pin slot. Never reuse the old cotter pin or seal.
For most trailer owners, buying a pre-greased hub and drum assembly and swapping the whole unit is faster, cleaner, and costs only slightly more than buying parts separately. You get new bearings, new races, new seal, and new grease already installed. Call us at (517) 225-1991 and we'll identify the right assembly for your axle.
What You Need
- NLGI #2 polyurea or lithium complex wheel bearing grease
- New grease seal β never reuse the old one β removal deforms it
- New cotter pin β never reuse
- Bearing kit matching your axle (see below for part numbers)
- Socket for spindle nut (typically 1-1/4" for 3.5K axles)
- Torque wrench, rubber mallet, flat-blade screwdriver, shop towels
- Solvent or brake cleaner for cleaning
Bearing Part Numbers by Axle Size
| Axle Capacity | Inner Bearing | Outer Bearing | Notes |
|---|---|---|---|
| 2,000β2,200 lb | L44643 | L44643 | BTR spindle β both bearings same size |
| 3,500 lb (#84 spindle) | L68149 (1.378" ID) | L44649 (1.063" ID) | Most common dump and utility trailer |
| 5,200β6,000 lb | 25580 (1.781" ID) | 15123 (1.063" ID) | 5-bolt pattern hubs |
| 7,000 lb | 25580 | 14125A | Confirm with your axle stamp |
Step-by-Step Repack Procedure
- Jack and Support the Trailer Safely
Jack the trailer until the wheel clears the ground. Place jack stands under the frame β never work under a trailer supported only by a floor jack. Confirm stability before getting underneath.
- Remove the Wheel
Loosen lug nuts before jacking (easier when tire is on the ground), then remove once raised. Set the wheel aside.
- Remove the Grease Cap
Tap around the edge of the grease cap with a rubber mallet until it pops off. On EZ-Lube hubs, there may be a rubber plug to remove first.
- Remove the Cotter Pin and Castle Nut
Straighten the cotter pin legs with needle-nose pliers and pull it out. Then remove the castle nut and the flat washer behind it. The outer bearing will often slide out as you pull the hub off β be ready to catch it.
- Slide the Hub Off the Spindle
Pull the hub straight off. The outer bearing may stay with the hub or fall free. The inner bearing stays inside the hub, held by the grease seal. Set the hub face-down on a clean surface.
- Remove the Grease Seal and Inner Bearing
Pry the grease seal out from the back of the hub using a large flat-blade screwdriver. Discard it immediately β it's single-use. Lift out the inner bearing. Inspect it before cleaning.
- Clean Everything Thoroughly
Use brake cleaner or solvent to remove every trace of old grease from: both bearing cones, the hub interior, the hub races (the smooth rings the bearings ride in), and the spindle. Dry with a clean lint-free rag. The metal should be surgically clean before inspection.
β Never use compressed air to spin a dry bearing β rollers can come apart or suffer microscopic damage.
- Inspect Bearings and Races
Inspect every roller on both bearings for pitting, spalling, flat spots, or corrosion. Run your finger around the inside of each race β it should feel perfectly smooth. Replace bearings and races as a matched set (cone + cup together). If the race shows any damage or the cone shows any defect, replace both.
- Pack the Bearings with Fresh Grease
Place a generous amount of NLGI #2 grease in your palm. Press the wide end of the bearing cone into the outer edge of the grease pile, forcing grease up through the gaps between the rollers. Rotate and repeat around the entire bearing until grease is visible between every roller. Both inner and outer bearings need to be fully packed.
- Install the New Grease Seal
Apply a thin bead of RTV sealant to the outside metal edge of the new seal (not rubber-encased seals β those don't need it). Tap the seal into place squarely using a wooden block β never a metal hammer directly on the seal. The lip of the seal faces inward (toward the bearing).
- Reinstall Hub, Bearings, and Castle Nut
Slide the inner bearing back into the hub against the seal. Slide the hub onto the spindle. Install the outer bearing, then the flat washer, then the castle nut finger-tight.
- Set the Castle Nut β Critical Step
This is the most important part of the job:
- Spin the hub and torque the castle nut to 50 ft-lbs while the hub rotates β this seats the bearings.
- Loosen the castle nut completely to remove all preload.
- Tighten finger-tight until just snug.
- Back off slightly until the first cotter pin slot aligns with the hole in the spindle.
- Insert a new cotter pin. Bend the legs over to secure.
The nut should be free to rotate with only the cotter pin restraining it. There should be barely perceptible end-play in the hub β the hub will spin freely but with no looseness.
- Install Grease Cap and Wheel
Tap the grease cap back on firmly. Reinstall the wheel and torque lug nuts in a star pattern. After the first 50 miles of use, re-torque the lug nuts.
Castle nut too tight: Bearings bind, overheat, and fail within miles.
Castle nut too loose: Hub wobbles, destroys the spindle, and can cause wheel separation.
Reusing the old seal: Seal is deformed during removal and will leak immediately.
Reusing the old cotter pin: Metal fatigues β use a new pin every time.
Mixing new bearings with old races: New cones on worn races wear out immediately. Always replace as a matched set.
