Dangers of Wheel Widening

Installing New Tires
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Custom car shops and wheel works stores often receive calls or visits from customers who ask if the current steel or alloy wheels can be widened to allow them to equip the car with wider tires. 

This is a highly controversial practice. There are tire and wheel shops who routinely offer this service, and customers often make use of this practice as a means to save money over buying new wheels at the width they want. Other wheel shops, though, will flat out refuse to even consider this practice, for reasons that are quite logical. And yet, some car owners not only insist on having this done but may even consider doing it themselves with home welding tools. 

Before you consider having this done to your original equipment (OE) wheels, it's best to consider the possible dangers. 

How Wheels Are Widened

When a factory wheel is widened to accept a wider tire, the process involves sawing the wheels in half parallel to the barrel and then welding in a piece of metal between the two halves. In other words, the joint between the two edges is simply pressed together with no lateral support at all. Such a configuration might be enough to hold air on a show car that never gets driven anywhere, but many experts believe that any real road impact could destroy a wheel modified in this way. 

Why Wheel Widening Is Dangerous

Car owners, in their zeal to modify a beloved automobile on the cheap, neglect to consider why this wheel widening is a bad idea. In some cases, a car's wheel well might simply be too narrow to accept a wider tire without scraping against the suspension. 

More to the point, though, is the fact that the kind of welded joint used to widen wheels may have good lateral strength but very weak sheer strength. Its ability to resist the kind of common stress applied at a 90-degree angle to the weld—such as hitting a pothole or a manhole cover—is very, very low. The resulting failure of the weld will cause the tire to deflate instantaneously and can potentially kill you or someone else. 

Buying New Wheels Is the Better Option

Reputable wheels shops will often show the car owner why it makes more sense to simply buy new wheels. The cost of having your existing wheels customized is somewhat less than buying new, wider wheels, but the dangers of the practice are well documented and simply not worth the risk.

If these very good arguments don't convince you, and you remain determined to save money at the expense of safety, make sure to consult a shop that has long experience with the practice and a willingness to guarantee their work. And under no circumstances should you attempt this yourself in a home workshop.