trailer on tires

Overloading and Underinflation

What are overloading and underinflation, and why do they matter?

Overloading is when a vehicle or trailer’s weight exceeds its tires’ load-carrying capacity. In other words, it’s when your tires are carrying more weight than they can safely handle.

Underinflation is when the tire air pressure is too low to support the weight of the vehicle.

Together, overloading and underinflation are the main causes of tire blowouts and tire failures.

Effects of Underinflation and Overloading

Effects of Underinflation and Overloading

When a tire is overloaded or underinflated, it can’t grip the road properly; this leads to poor handling, vehicle instability, and reduced fuel economy. On top of that, overloading and underinflation lead to heat buildup in the sidewall and tread area, potentially causing serious problems. The more an overloaded/underinflated tire is driven on, the more it heats up, which can cause the structural components to break down and lead to tire failure.

If a tire has been driven on for an extended period while overloaded and/or underinflated, you should have a tire professional inspect it for related damage or deformation. If any damage to the tire is found, it should be removed from service immediately and replaced.

When replacing your tires, be sure that the new tires meet or exceed the minimum requirements for load-carrying capacity. Conversely, when loading a vehicle make sure that you don’t add more weight than can be supported by the tires.

How to Avoid Underinflation and Overloading

Be sure to check the air pressure in your tires regularly. We recommend checking the air pressure at least once a month. Your tires’ maximum inflation and load-carrying capacity can be found on their sidewalls. Keep in mind this is the maximum inflation, and not necessarily the recommended pressure for the tires on your vehicle.

Your vehicle’s recommended cold air pressure can almost always be found on the door placard. Otherwise, check the glove compartment or the owner’s manual.

How to Avoid Underinflation and Overloading


Of course, it is always safe to have one of our experts check the air pressure in your tires, and we'll inflate and inspect them for free. If you have any questions or need any assistance, stop by your local Discount Tire and we'll get you taken care of.

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