What Are Trailer Bearings And Races
Tuesday, April 23, 2013 — No Comments Yet
INNER RACE / OUTER RACE (AKA CUP) The inner and outer race come pressed-in new hubs. They provide a smooth surface on which the bearings spin. In the case where a race is being replaced on an older hub, the correct size can be selected either by:
- looking for the small stamped part number on the race
- measuring the old race and finding the match (see measurement chart)
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If the bearings are being replaced on a hub, the races should be replaced as well, even if they don't show sign of wear. Signs of wear & definite need of replacement include nicks, and discoloration. When new races are installed in the hub, the surface of the race should be greased to ensure a smooth and easy running surface for the bearings.
What makes them 'inner' and 'outer'? One is closest to the spindle, the 'inside' part of the hub, and the other is towards the 'outside' of the hub.
INNER BEARING / OUTER BEARING (AKA CONE) Bearings sit inside the race, and the small ''rollers' allow the rotation of the hub on the spindle. Like races, most bearings are stamped with a reference number that can be used to easily identify its inside diameter. If it is a new hub that does not come packed, you can use the race part number or race measurements to find the matching bearing.
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CLICK ON THE LINK TO VIEW OUR SELECTION OF TRAILER BEARINGS AND RACES. If you need help selecting an item, contact our team!