Learn how to protect your "boat trailer bearings" , and if needed where to buy replacements. Why is one of the smallest parts of the boat trailer one of the most critical to keep clean, greased and properly working? It is the bearings that allow the trailer wheels to turn freelly, with no friction, no heat build up and keep turning for thousands of miles. If dirt or water get into the bearings and replace the grease then you are primed for bearing failure. This can result in your wheel not turning, and even coming off the axle. This would not be good.

pretty sure autos and trailers are the same. If your inner hub seal was leaking or gone the grease would run out onto your brakes and wheels. Most guys use bearing buddies to make sure the grease will cover the bearing compleatly. Bearings warm up in use, this is normal. As they warm the air inside the hub expanes, the bearing buddy is spring loaded and allows for this expansion. Some hub seals are double lipped sealing in both directions and some more expensive seals are two piece with the sealing surface intergrated in the seal. 

Both of these types of seals are not something you see on a trailer but you can buy them to fit your application at most bearing houses. Most axles have a thin stainless sleeve called a seal wiper. This wiper provides a sealing surface. Modern bearing lube doesn't flow like the hi fiber grease of the 60s and bearings last longer then they did back in the old days. All bearings still need to be checked for runout and preload. boat trailer nsk bearings wear faster because trailers have smaller wheels and guys drive to fast for the wheel size. This overheating could cause the water in a hub with a bad seal to dry out faster so maybe it's a wash.

The problem with boat trailer bearingsis that when you back the boat in the launch,the warm hub is cooled rapidly creating a slight vacuum in the hub.The seal that is designed only to keep grease in, will let water enter the hub.A spring loaded bearing buddy keeps a small amount of pressure in the hub to counteract the vacuum.A good investment? Yes.

Boat trailers can be subjected to some very harsh elements and chemicals. Considering the environment they work in, it is no surprise when the trailer wheels and timken bearings start to show signs of wear and tear. Saltwater can ruin delicate needle or ball bearings in a very short time. Dry or contaminated boat trailer bearings can fail during a long or even short trip to the recreational area, spoiling the outing for everyone. Trailer wheel bearings should be inspected and serviced more often than any other part on the trailer.

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