I have read so many different opinions about whether to repack wheel bearings or use the external grease nipples. Some things I have read: that wheel bearings should be repacked every 12 months, just inspected every 12 months, external grease application is sufficient, and if you add too much grease through the external nipples you could blow out the seals. What is your recommendation on wheel bearing maintenance? Thank you. —Leigh, 2022 Grand Design Imagine 22MLE
It seems everyone has an opinion on when to repack trailer wheel bearings—some even have two opinions! The recommended repack and inspection depends on the type of bearing/axle assembly and usage.
This product, in my opinion, has the most widespread misinformation on the internet. I see posts that state you keep pumping grease periodically into the Zerk fitting until you see grease, or that it doesn’t need to be resealed for 5 years!
According to the Bearing Buddy site, grease is added until it pushes the piston out, which protects the inside of the hub from the outside environment. This is designed to keep water from entering when the axle is submerged in water, such as loading and unloading a boat. An automatic pressure relief feature prevents overfilling, which means any additional grease will ooze out around the ring.
What is interesting is the etrailer.com website that sells the Bearing Buddy has two completely different recommendations. One of the “experts” states that if you maintain the grease, you do not need to repack and inspect periodically. Another states that bearing manufacturers still recommend inspection and repacking, as necessary, every 12 months or 12,000 miles.
What the Bearing Buddy is useful for
When you look at a diagram, it is clear the grease only gets behind the Bearing Buddy O-ring and seal and not to the bearings. So, it is designed to prevent water from getting to the bearings and seals. All the documentation on the site talks about how the bearings get hot driving down the road and then submerging them in cold water acts as a vacuum drawing in moisture. The Bearing Buddy is an add-on cap, not a bearing assembly. The main advantage of the Bearing Buddy is the moisture protection, as most axle assembly manufacturers recommend removing and repacking the bearing and seals after every water immersion. Not with Bearing Buddy.
I ran a company called Easiwash for the past 10 years. We had three trucks and trailers, each putting on more than 100K miles annually. I can verify the Bearing Buddy did not lubricate the inner bearings and had to be repacked periodically. We used an Infrared Temperature Gauge to determine what heat was being generated, as a sudden spike in temperature would tell us a lot about what was happening inside the hub assembly and brake drums.
E-Z Lube by Dexter
The E-Z Lube spindle allows new grease to be pumped into the Zerk fitting. It then flows through the hollow opening in the spindle to the inner bearing, forcing old grease out and pumping new grease in. This is one of the best methods to periodically add new grease. However, they still recommend pulling the bearings out and visually inspecting and repacking, if necessary, once a year or every 12,000 miles.
Nev-R-Lube By Dexter
Dexter’s Nev-R-Lube bearings are comprised of opposite tapered bearings designed into a sealed, precision ground cup. As stated, they never need lubrication. However, they do recommend removing and inspecting the bearings once a year. Unlike the Bearing Buddy and E-Z Lube, the Nev-R-Lube system is not designed to be submersed in water.
So, you can see there are different recommendations for different systems. However, all recommend visually inspecting once a year, and most do not recommend a pneumatic grease gun as it can blow out the seals.
You might also enjoy this from Dave
How many miles before I need to repack RV’s wheel bearings?
Is there any basic mileage recommendation for how often wheel bearings on a travel trailer should be repacked? —Andy, 2022 Salem 27RK
Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”
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I pull the hubs and drums every year. The first thing I want to see is the seal. I check it for flexibility and that it is doing it’s job. If I find one “ify” I change them all and clean and pack the bearings. I have a friend who didn’t think that was all that necessary and he has replaced both axles because he lost a seal. No matter what kind of a greasing system you have, the seal can be the weak link. My trailer is an 05 and lots of miles. Still running on the original bearings.
I have the Dexter EZ Lube system on my two wheels. Bought the trailer new in 2013. I have always supported the 12,000 mile/12 month rule. That said, I do the EZ lube two years in a row, then a full hand repack and inspection. When using the EZ lube zerk fittings I jack up the wheel and slowly spin it while VERY SLOWLY pumping the grease in until the new grease shows. I have never blown out the inner seal using this method. On the third year everything gets removed, cleaned, inspected and repacked, replacing the inner seal as it gets destroyed during removal.Bearings have never shown any pitting or wear…but then, I’ve only averaged 3600 per year. YMMV.
I agree with Dave and the manufacturers of the axles. Once a year or 12,000 miles whichever is first is a rule of thumb.
50 years ago. brakes lasted about 20,000 miles so when you went and got your brakes done the mechanic repacked the wheel bearings at the same time.
When disc brakes came out the wheel bearings were still repacked but with high temp grease because of the higher temperature created by disc brakes.
In the late 1980’s and early 1990’s car manufacturers came out with sealed bearings which last about 100,000 miles or more. No need to repack wheel bearings. Just replace.
Trailer axles are using 100-year-old technology.
The idea of pushing grease through a wheel bearing and into a second wheel bearing without blowing out a seal is just plain stupid.
Do the maintenance and have enjoyable travels without break downs.
I. Installed disc brakes and don’t worry about grease. I’ve got a bad seal on one wheel and have ez lube. Pump grease in excessively. Who cares. The rotor has never gotten any grease on it. Seems everything lines up just right and grease slings right off and never touches rotor.
Someday I’ll get around go changing seal, but not in a hurry.
How often should you grease wheel bearings? When is the last time you did your car or tow vechicle. Ever?
HI Tom: I’d be in a hurry if it were me. Seals are two way affairs – enter dirt and water and road salt etc to your grease and see what that does to your bearings in a very short order! Seals are inexpensive compared to a bearing replacement or worse – a failure.
Before bearing buddies when launching my boat I would take a pail and pour lake water over the wheel to cool down the hub so as to not create a vacuum. And it’s not just pneumatic grease guns, any grease gun can blow out a seal. Blow out a seal and you get grease on your brake shoes and then they must be replaced. Just do it right and repack those bearings.
If you buy a new trailer, ask the dealer to lube the bearings before it leaves the lot. Most bearings only have the minimum amount of grease that was applied by the bearing manufacturer.
Ask the dealer to what? Are you kidding, they can’t even do a new vehicle inspection right. Doing a bearing grease packing actually takes some skill!