How Trailer Bearing Protectors Work

Boaters need trailer bearing protectors to keep their boats running smoothly.
Boaters need trailer bearing protectors to keep their boats running smoothly.
Logan Mock-Bunting/Getty Images

­Trailer bearing protectors are spring-loaded metal caps th­at replace the dust caps on a trailer's hubs. This is especially true of boat trailers that enter the water when the boat is launched. The protectors keep dirt and water out of the trailer bearings and keeps grease inside the hub, even when submerged. Trailer bearing protectors have a spring inside to keep constant pressure on the trailer bearings in any condition, wet or dry. This keeps contaminants out while keeping towing and bearing grease in, prolonging the life of the tow bearings and reducing the need to repack or replace them every year or two. Dry or dirty bearings wear down over time, keeping the hubs from rotating freely.

­In addition to the spring-loaded bearing protectors, additional protective equipment can further seal the bearings against road grime. Like the protective cover on the nose of a sports car, these additional caps are usually called "bras." They are cheap and easy to install over the bearing protectors. All told, the protective equipment will cost about $25 to $50, depending on the size of the towing trailer's hubs. Bearing protectors alone cost $20 to $40.

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As inexpensive as this equipment is, this one-time cost might actually save you money in the long run. Read on to find out how.

Purpose of Trailer Bearing Protectors

Two Floridians load their boat onto a trailer as they wait for Hurricane Wilma. Trailer bearing protectors should keep the boat's hubs clean in inclement weather.
Two Floridians load their boat onto a trailer as they wait for Hurricane Wilma. Trailer bearing protectors should keep the boat's hubs clean in inclement weather.
Carlo Allegri/Getty Images News

­The purpose of trailer bearing protectors is right in the name: They protect the bearings by keeping foreign particles and water out. But why pay for additional towing equ­ipment if bearings are cheap and easy to replace?

Without this protective equipment, you'll need to replace tow bearings as often as once a year, due to wear from road debris and grease that has washed away while launching a boat. This will cost about $15 to $25 for a complete kit, not including your time (if you're handy with hubs and bearings) or the cost of labor at the local mechanic's shop. Kits generally include enough to repair only one hub: two bearings, two races for the bearings to roll against, one grease seal, and one cotter pin.

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Bearing protectors can be found for between $20 and $40, plus a few dollars for the bras to keep them clean. Bearing protectors can keep bearings greased and free of debris and water for years, making it more cost-effective to protect bearings than to replace the hubs or bearings periodically.

For more information on trailer bearing protectors, please see the links on the next page.

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More Great Links

Sources

  • Cabela's (10/15/2008) http://www.cabelas.com/prod-1/0001882013059a.shtml
  • Champion Trailers (10/15/2008) http://www.championtrailers.com/bearing_protectors.html
  • Eastern Marine (10/15/2008) http://www.easternmarine.com/em_store/hubs/
  • Kodiak Trailer (10/15/2008) http://www.kodiaktrailer.com/content/view/15/32/

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