Hub Caps

A hubcap or wheel cover is a decorative disk on an automobile wheel that covers at least a central portion of the wheel. Cars with stamped steel wheels often use a full wheel cover that conceals the entire wheel. more...

Cars with alloy wheels or styled steel wheels generally use smaller hubcaps, sometimes called center caps.

Early hubcaps were very small, sometimes merely covering the grease bearing of the wheel. These snap onto bulges on the wheel, and to change the wheel they are pried off with a tool resembling a very large slotted-tip screwdriver. This differs from the spinners that serve the same purpose for racing cars and those cars with wire wheels, which were designed to be quickly unthreaded by hand. Most hubcaps were once made of chrome-plated steel or stainless steel.

The rest of the wheel was originally of wood or many fitted metal parts. When pressed steel wheels became common by the 1940s, these were often painted the same color as the car body. It was these steel wheels that had the lug nuts that the hubcap expanded in size to cover. The next development was, as an option on more expensive cars, a chrome-plated trim ring that clipped onto the outer rim of the wheel, right at the tire. Finally came the full wheel cover, which of course covered the entire wheel. By this time, specialty wheels of magnesium or aluminium alloy had come on the market, and wheel covers were a cheap means of imitating the styling of those. Plastic wheel covers appeared in the 1970s and became mainstream in the 1980s. Plastic has largely replaced steel as the primary material for manufacturing hubcaps.

Often a hubcap will bear the trademark or symbol of the maker of the automobile or the maker of the hubcap. Early hubcaps were often chrome plated, and many had decorative, non-functional spokes. Hubcaps were immortalized in the Art Deco styling of the spire of the Chrysler Building in midtown Manhattan.

Part of the lore of hubcaps is that on bad roads they have a tendency of falling off due to hitting a bump. In the southwest of the U.S., and in Mexico, there were lots of automotive garages whose walls were decorated with all sorts of hubcaps that had fallen off in the vicinity; they were often for sale. This problem persists today in spite of the many different retention systems that have been engineered. Hubcaps generally use either clip-on retention, where some type of spring clip engages a groove in the wheel, or bolt-on retention, where a threaded fastener retains the hubcap. Clip-on hubcaps tend to pop off suddenly when the wheel impacts a pothole or curbstone, while bolt-on hubcaps are more likely to vibrate loose over time, and tend to rattle and squeak.

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