Why Do My Bearings Keep Wearing Out?

Rick Sosebee
by Rick Sosebee

Why do my wheel bearings keep wearing out? This is what one frustrated Yamaha Rhino owner wants to know and the ATV AnswerMan is on the case.

Here is exactly what the reader asked the ATV AnswerMan, followed by his response:

We own a 2006 Yamaha rino 660 with a high lifter suspension lift and 28 inch tires and the wheel bearings seem to need replacing every year. It all started when I had one steer wheel began to swerve and I wasn’t turning the steering wheel. I knew something was wrong but I didn’t know just how much I would find until I actually started looking. I jacked the front of the rino up and low and behold the right front wheel almost fell off. It just dropped out at the top about 2 inches it seemed. Even though this was a problem I then noticed the steering was really loose and would turn about an inch without moving the steering wheel. So, I changed the steering rack (what a pain) because it wasn’t the tie things on the ends but the whole rack. That fixed one problem and then on to the wheel. The big bearings that hold the axle in were shot too. I bought some bearings off ebay that said “quality replacement bearings” but guess what.. After only about 9 months I’m in the same boat again with a worn out front end. So I paid for some really expensive supposed to be Yamaha bearings and again im looking at doing this again after only about a year. What makes this stuff wear out so fast?

I know the pain of replacing steering knuckle bearings in the Yamaha Rhino. I too had tremendously bad luck just replacing the bearings, always in hopes that this would be the last time. I am not sure what type of terrain you ride in, but it sounds like you might be in a wetter climate according to the tires and lift. I can say with certainty that mud and water will find its way into the seals and bearings like nobody’s business. You must clean this out after every ride. I also know that the cheaper the bearing is, especially in some eBay stores, the shorter period of time it will last. I am not saying that eBay is not a good place to shop, but if the price seems too good to be true then consider that first and foremost! You might be better off buying trusted quality like genuine Yamaha parts from a dealer.

So, onto the issue at hand; I found that most bearings wore out prematurely because of several things. The first being that the seals on the rear of the steering knuckle were compromised or worn out. just replacing the bearing is not an option. Get those seals too and make sure they are installed squarely and not damaged in anyway. Also, the mud we love to play in gets behind the seals sometimes or debris in the thick gnarly mud can pry open the seal that rides on the outer axle joint and allow its evil friend, water and junk, in to start the problem. A bad outer CV cup surface (this is the housing that the outer joint is inside of) with gouges or scrapes into the steel itself can also let water slip in.

Now I know you might say “but these are sealed bearings” and hell I know that, but they must not be sealed very good on any of them because everything I find inside of the bearing is a rusted mess! Be sure to wash out these areas well with a garden hose. It’s too easy to force junk in the seals with a power washer so use care there as well. Lastly, I changed the bearings in my Rhino a few times and found that the knuckle was actually worn out. I replaced the entire steering knuckle (It even comes with ball joints) and for the cost of a new factory knuckle you will save about four bearing changes. Just food for thought.

Rick Sosebee
Rick Sosebee

Whether he is in Mexico covering the Baja 1000, building ATVs for local racers, or out enjoying the trails, Rick’s passion shows in his stories. Learning to wrench his own machines from his grandfather, Rick also has an undying appreciation for the mechanics of off-road vehicles. Do not let the dirt and mud fool you, though, as Rick also has a deep love for street cars.

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