Greasing trailer hubs regularly is one of the most important maintenance tasks for trailer owners. Properly lubricated hubs will lead to longer lasting hubs, wheels, and brakes. Neglecting to grease hubs frequently enough can result in seized bearings, ruined hubs, damaged brakes, broken axles, and potential safety hazards from wheel detachment. Greasing intervals depend on trailer type, axle type, and driving conditions. With regular inspection and maintenance, most trailer hubs should be greased at least once per year, but intervals can range from every 6 months to every 100,000 miles depending on usage.
Page Contents
- 1 What are trailer hubs and why do they need to be greased?
- 2 Factors that determine greasing frequency
- 3 Greasing procedure
- 4 Greasing intervals by trailer type
- 5 When to grease after wheel removal
- 6 Signs that hubs need greasing
- 7 Consequences of neglected hubs
- 8 Best practices for trailer hub maintenance
- 9 Conclusion
What are trailer hubs and why do they need to be greased?
Trailer hubs contain the wheel bearings that allow the wheels to spin freely around the axle. Inside the hub is a packed grease cavity that surrounds the bearings. This grease lubricates and protects the bearings from wear and overheating as they spin. It also keeps water and contaminants out of the bearings.
Without adequate grease, the bearings rotate directly against the metal hub which generates damaging heat and friction. The grease breaks down over time and needs to be replaced periodically to maintain proper lubrication. The regular re-greasing interval depends on the trailer usage, axle type, and driving conditions.
Factors that determine greasing frequency
There are several key factors that impact how often trailer hubs need fresh grease:
Trailer type
* Utility trailers – Used infrequently for light duty hauling require less frequent greasing than heavy use trailers. Only need greasing every 1-2 years if used lightly.
* Enclosed cargo trailers – Used for hauling equipment, household goods, cars etc. Require greasing at least annually.
* Horse/livestock trailers – Frequent use and vibration from traveling require more frequent greasing every 6-12 months.
* Boat trailers – Frequent immersion in water requires more corrosion protection with annual greasing.
* Travel trailers/5th wheels – Regular movement and vibration need annual greasing.
Axle type
* Standard axles – Only need annual greasing.
* E-Z Lube/Dexter axles – Special zerk fittings allow easy greasing by pumping new grease which pushes out old grease. Only need greasing every 1-2 years.
* Sealed bearings – Come pre-packed with grease and sealed to keep contaminants out. Require less frequent greasing every 2-5 years depending on use.
Mileage and driving conditions
* Less than 3,000 miles/year – Only need greasing annually.
* 3,000-7,000 miles/year – Recommend greasing every 6-12 months.
* Over 7,000 miles/year – Increase frequency to every 6 months or 30,000-50,000 miles.
* Frequent starts/stops – Causes more wear so grease more frequently.
* High speeds – Generates more heat so increase greasing frequency.
* Wet driving – Corrosion risk so grease annually minimum.
* Off-road use – Vibration causes wear so grease every 6-12 months.
* Salt exposure – Corrosion risk needs increased greasing frequency.
Greasing procedure
Greasing trailer hubs is a quick process that can be done in under 5 minutes per hub if you follow these steps:
1. Block wheels to prevent rolling and lift the axle if needed.
2. Remove hubcap or rear drum to access zerk grease fitting.
3. Wipe zerk fitting clean so you don’t inject dirt and debris.
4. Attach grease gun loaded with #2 lithium complex, extreme pressure grease. Avoid automotive chassis grease.
5. Slowly pump grease in while rotating wheel. Stop when new grease is ejected indicating cavity is full. 2-3 pumps is typically sufficient.
6. Install hubcap or drum and lower trailer. Wipe off excess grease.
Greasing intervals by trailer type
Here are the recommended greasing intervals for different trailer types:
Utility trailers
| Usage | Greasing interval |
| Occasional light duty use | Every 2 years |
| Frequent moderate duty use | Annually |
| Heavy duty construction use | Every 6-12 months |
Enclosed cargo trailers
| Usage | Greasing interval |
| Occasional recreational use | Annually |
| Frequent business use | Every 6-12 months |
Horse/livestock trailers
| Usage | Greasing interval |
| Occasional recreational hauling | Annually |
| Frequent long distance hauling | Every 6 months |
Boat trailers
| Usage | Greasing interval |
| Less than 20 launches annually | Annually |
| More than 20 launches annually | Every 6 months |
Travel trailers/5th wheels
| Usage | Greasing interval |
| Less than 5,000 miles annually | Annually |
| 5,000-10,000 miles annually | Every 6-12 months |
| Over 10,000 miles annually | Every 6 months |
When to grease after wheel removal
Anytime a trailer wheel is removed for tire service or brake maintenance, it is critical to repack the bearings with fresh grease before reinstalling the wheel. This ensures proper lubrication and prevents bearing damage from contaminants entering the exposed hub.
Follow this procedure for repacking after wheel removal:
1. Thoroughly clean bearings, races, and hub components in solvent. Inspect for wear or damage.
2. Pack bearings fully with fresh grease by smearing grease between rollers or using a bearing packing tool.
3. Install inner bearing into race and pack hub cavity with grease.
4. Install grease seal and outer bearing.
5. Install hub and adjust bearings per manufacturer specifications.
6. Check that the bearing cavity was filled with grease by verifying grease ejected when installing hub.
Signs that hubs need greasing
In addition to adhering to regular greasing intervals, be alert for these signs that your trailer hubs need fresh grease:
– Elevated hub temperature after driving indicates bearings lacking grease lubrication.
– Weeping or cracked grease seals indicating contaminated or insufficient grease.
– Bearing noise including grinding, squeaking or rumbling sounds.
– Loose bearing adjustment requiring frequent tightening.
– Excessive bearing wear upon inspection.
– Rust or corrosion on hub components signaling water contamination of grease.
– Wheel end vibration or shimmying sensations during driving.
Address any of these issues immediately by repacking hub with fresh grease to prevent further component damage.
Consequences of neglected hubs
Neglecting proper trailer hub greasing leads rapidly to a number of problems including:
Seized bearings
Lack of lubrication causes bearings to overheat and seize to the hub stopping rotation. Requires replacement of bearings.
Damaged bearings
Insufficient grease results in premature wear, flattening and corrosion of bearings.
Ruined hubs
Overheated bearings damage hub bearing seats causing extensive hub repairs or replacement.
Brake failure
Malfunctioning bearings misalign drum allowing shoes to contact drum damaging brakes.
Broken axles
Locked up hubs from seized bearings can shear axles or break axle welds.
Wheel detachment
Bearing failures lead to loose wheels that can detach at highway speeds.
Best practices for trailer hub maintenance
Follow these tips to keep your trailer hubs in peak condition:
– Establish a routine greasing schedule based on your usage according to manufacturer guidelines. Mark your calendar to stay on track.
– Use only high quality #2 lithium complex grease designed for wheel bearings. Avoid automotive chassis grease.
– When possible, carry a small grease gun and grease supply for roadside emergencies.
– Verify old grease is fully purged when pumping in new grease.
– Always repack bearings with fresh grease after any wheel removal.
– Inspect bearings, seals and hub components closely each greasing and look for damage.
– Check hub temperatures frequently by hand after driving to identify issues early.
– Consider installing oil bath hubs for heavy duty commercial use to prolong maintenance intervals.
Proper greasing practices maximize trailer safety, extend the life of hubs and bearings and prevent costly repairs down the road. Staying on schedule with routine re-greasing is the key to trouble-free trailer hub operation.
Conclusion
Greasing trailer hubs is an essential maintenance task to keep your bearings in smooth running condition. While most trailers only need annual greasing, the frequency depends on usage intensity and driving conditions. Utility and recreational trailers can often go longer between greasing while heavy use commercial units need servicing as often as every 6 months. Identify the recommendation for your specific trailer and axle type and stick to a routine schedule. Combine calendar-based greasing with alertness to signs of issues arising. With proper lubrication habits, your trailer hubs will provide you thousands of miles of reliable service. Neglected hubs quickly deteriorate leading to expensive repairs and safety risks that can be easily avoided through routine re-greasing.