Repacking wheel bearings on your travel trailer is essential to maintaining safe and reliable operation. This process involves cleaning, inspecting, lubricating, and reinstalling the bearings to ensure smooth wheel rotation and prevent costly (and potentially dangerous) axle failure.
Why Repacking Wheel Bearings Matters: The Authority’s Perspective
As a certified RV technician with over 20 years of experience, I’ve seen firsthand the catastrophic consequences of neglected wheel bearings. Proper lubrication is critical because it reduces friction between the moving parts of the bearing assembly – the rollers, races, and axle spindle. Without sufficient lubrication, these parts overheat, leading to accelerated wear, metal fatigue, and eventual seizure. A seized wheel bearing can cause a complete wheel lock-up, potentially resulting in a loss of control and a serious accident. Regularly repacking your wheel bearings isn’t just about preventative maintenance; it’s about ensuring the safety of yourself, your passengers, and other drivers on the road. It’s an investment in peace of mind.
Tools and Materials You’ll Need
Before you begin, gather the necessary tools and materials. Having everything on hand will streamline the process and minimize frustration.
- Jack and Jack Stands: Essential for safely lifting and supporting the trailer. Use appropriately rated jack stands.
- Wheel Chocks: For securing the opposite wheels to prevent rolling.
- Socket Set and Wrench Set: Including sockets to fit the axle nut and lug nuts.
- Bearing Packer: A tool designed to force grease into the bearing. Highly recommended for efficiency and thoroughness.
- Grease Gun: For applying grease to the Zerk fitting (if equipped) and for use with the bearing packer.
- Rubber Mallet: Useful for gently tapping components into place.
- Pry Bar or Screwdriver: For removing the dust cap and potentially prying stubborn bearings.
- Parts Cleaner and Rags: For thoroughly cleaning the bearings and other components. Brake cleaner can be used, but ensure adequate ventilation.
- Wheel Bearing Grease: Specifically formulated for wheel bearings. Check your trailer’s manual for the recommended type.
- New Cotter Pin or Castle Nut Retainer: Never reuse a cotter pin; always use a new one for safety.
- New Grease Seals: Replacing the seals is highly recommended during each repacking to prevent grease leakage and water contamination.
- Gloves: To protect your hands from grease and chemicals.
- Safety Glasses: To protect your eyes from debris and splashes.
- Torque Wrench: Crucial for properly tightening the axle nut to the manufacturer’s specifications.
- Optional: Brake Adjusting Tool: If you plan on inspecting your brakes while the wheel is off.
Step-by-Step Guide to Repacking Wheel Bearings
Follow these steps carefully to repack your travel trailer’s wheel bearings:
- Preparation: Park your trailer on a level surface, chock the wheels, and disconnect from shore power.
- Loosen Lug Nuts: Loosen the lug nuts on the wheel you’ll be working on before jacking up the trailer.
- Jack Up the Trailer: Use the jack to lift the trailer until the tire is off the ground. Place jack stands under the axle for safety. Never work under a trailer supported only by a jack.
- Remove the Wheel: Remove the lug nuts completely and carefully remove the wheel and tire assembly.
- Remove the Dust Cap: Use a pry bar or screwdriver to gently remove the dust cap from the hub.
- Remove the Cotter Pin and Castle Nut: Straighten the cotter pin and pull it out. Then, remove the castle nut.
- Remove the Outer Bearing and Washer: Carefully pull the hub assembly outward. The outer bearing and a washer should come out with it. Keep track of the order they came out.
- Remove the Hub: Fully remove the hub assembly from the spindle.
- Remove the Inner Bearing and Seal: Use a brass punch or similar tool and tap the inner bearing from the back side of the hub. Be gentle to avoid damaging the hub. The grease seal will come out with the bearing.
- Clean All Components: Thoroughly clean all components – the bearings, races (inner and outer), hub, and spindle – using parts cleaner and rags. Remove all traces of old grease and debris.
- Inspect All Components: Carefully inspect the bearings, races, and spindle for any signs of wear, damage, or corrosion. Look for pitting, scoring, or discoloration. Replace any worn or damaged parts.
- Pack the Bearings with Grease: Use a bearing packer to force grease into the bearings, ensuring that the grease is packed thoroughly between the rollers. If you don’t have a bearing packer, you can pack the bearings by hand, working the grease into the bearing until it comes out the other side.
- Install the Inner Bearing and New Seal: Lightly grease the outside of the inner bearing and gently tap it into the hub using a rubber mallet. Install a new grease seal, making sure it is seated properly and flush with the hub.
- Install the Hub Assembly: Carefully slide the hub assembly back onto the spindle.
- Install the Outer Bearing and Washer: Grease the outer bearing and install it into the hub. Install the washer.
- Install the Castle Nut: Install the castle nut and tighten it until snug.
- Adjust the Bearing Play: Back off the castle nut until it is loose. Then, tighten the nut to the manufacturer’s specified torque (usually very low, often around 12-15 ft-lbs). Next, back the nut off slightly until the nearest cotter pin hole aligns with a slot in the castle nut. Never tighten the nut further to align the cotter pin hole.
- Install a New Cotter Pin: Install a new cotter pin and bend the ends to secure it in place.
- Install the Dust Cap: Gently tap the dust cap back into place.
- Reinstall the Wheel: Mount the wheel and tire assembly.
- Tighten Lug Nuts: Tighten the lug nuts in a star pattern to the manufacturer’s specified torque.
- Lower the Trailer: Carefully lower the trailer and remove the jack stands.
- Final Lug Nut Check: Recheck the lug nuts after driving a short distance.
Frequently Asked Questions (FAQs)
Here are some common questions about repacking wheel bearings on travel trailers:
What type of grease should I use for my travel trailer’s wheel bearings?
It’s crucial to use a high-quality wheel bearing grease specifically designed for high temperatures and heavy loads. Most RV manufacturers recommend a lithium-based or synthetic grease with an NLGI Grade 2 rating. Consult your trailer’s owner’s manual for specific recommendations.
How often should I repack my travel trailer’s wheel bearings?
Generally, it’s recommended to repack your wheel bearings every 12 months or 12,000 miles, whichever comes first. However, if you frequently tow in harsh conditions (e.g., dusty roads, heavy rain), you may need to repack them more often.
Can I over-grease my wheel bearings?
Yes, over-greasing can be detrimental. Over-greasing can cause the seals to blow out, allowing grease to escape and potentially contaminate the brake shoes. It can also create excessive pressure, leading to premature bearing failure.
What are the signs of worn or failing wheel bearings?
Common signs include: unusual noises (grinding, squealing, or roaring) coming from the wheels, excessive play in the wheel when jacked up, uneven tire wear, and excessive heat coming from the hub.
Can I repack my wheel bearings myself, or should I take it to a professional?
If you are comfortable working on mechanical systems and have the necessary tools and knowledge, you can repack your wheel bearings yourself. However, if you are unsure or uncomfortable, it’s best to seek the assistance of a qualified RV technician.
What is the purpose of the cotter pin?
The cotter pin is a crucial safety component that prevents the castle nut from loosening. Always use a new cotter pin each time you repack your wheel bearings.
Do I need to replace the grease seals every time I repack the wheel bearings?
Yes, it is highly recommended to replace the grease seals every time you repack your wheel bearings. Old seals can become brittle and cracked, allowing grease to leak out and contaminants to enter.
What happens if I don’t repack my wheel bearings?
Neglecting to repack your wheel bearings can lead to bearing failure, which can cause the wheel to lock up, potentially resulting in a serious accident. It can also lead to costly repairs, including replacing the axle.
What is a bearing packer, and do I need one?
A bearing packer is a tool that forces grease into the bearing more effectively than packing by hand. While not essential, it makes the job easier and ensures that the bearings are properly lubricated.
How do I properly torque the axle nut?
The correct torque for the axle nut is crucial for proper bearing adjustment. Consult your trailer’s owner’s manual or the axle manufacturer’s specifications for the correct torque value. Always use a torque wrench to ensure accurate tightening.
How do I know if my bearings are properly adjusted?
After tightening the axle nut to the specified torque and installing the cotter pin, the wheel should spin freely without excessive play. There should be a slight amount of endplay (a very small amount of movement back and forth). If the wheel is too tight or too loose, re-adjust the nut according to the manufacturer’s instructions.
Where can I find the manufacturer’s specifications for my travel trailer’s wheel bearings?
The manufacturer’s specifications can usually be found in your trailer’s owner’s manual. If you don’t have the manual, you can often find it online or contact the trailer manufacturer directly. You can also contact the axle manufacturer directly if you know who made the axles.
By following these steps and FAQs, you can confidently repack your travel trailer’s wheel bearings and ensure safe and reliable towing for years to come. Remember, safety should always be your top priority.