We are not experts on tires to tell you what the most common outcome is when driving on an underinflated tire but we can tell you that it is unwise to do so and can lead to dangerous driving situations for the driver of a vehicle with underinflated tires.
Underinflated tires wear out the tire tread prematurely and unevenly, wastes gas and creates deadly driving situations. The life of your tires decreases by 10% for every 10% underinflated they are. Stopping distance generally increases with lower tire pressure. Underinflated tires also increase the potential for hydroplaning.
An underinflated tire can lose traction more easily than one which is properly inflated, which can cause skidding during braking and wheel spin when accelerating. When a tire is underinflated it causes more of the vehicle's weight to be concentrated on the tread that is located under the sidewall instead of the weight being spread out evenly across the full width of the tire. This means that as the tire rotates around the sidewall is continually flexed and heats up. This situation can affect both the performance of the car and safety of the driver and passengers. Besides degrading the handling of the vehicle a tire that is very low on air has an increased risk of tire failure and a blow out due to the stress from the constant flexing of the sidewall and the heat buildup.
AAA as well as the National Highway Traffic Safety Administration (NHTSA) recommends that you check the pressure in your tires as least once a month. If you do it on the first of each month it should get you into a regular schedule that you will not forget. When checking the pressure of the tires also make sure to give the tires a once over and look for uneven wear patterns and cut or bulging sidewalls. Irregular wear could signal the need for an alignment or replacement of worn suspension components from driving on underinflated tires.
Make sure when adding air to your tires to not overinflate them. If you add too much air to the tires it will not allow the desired full tire tread contact because the vehicle will be riding mainly on the center of the tread and will make the ride stiff and could again cause handling problems.
AAA research shows 1 in every 3 cars have a significantly underinflated tire (defined as 25% or more below placard). The NHTSA notes that 660 fatalities and 33,000 injuries occur every year as a result of low tire pressure related crashes. Their study found that 25% of the participants were not even aware of where to find the recommended tire pressure for their vehicle.
The tire placard tells you: the recommended tire pressure, the maximum weight (or load) your ride should carry, and recommended tire size. The tire placard is the label that is usually found inside your driver's side doorframe, on the edge of your driver's door, inside your glove box door, or on the lid of your trunk. You can also find the same information regarding the tire size, tire pressure and maximum weight load in your vehicle's owner's manual.
The NHTSA states that studies of tire safety show that maintaining proper tire pressure, observing tire and vehicle load limits (not carrying more weight in your vehicle than your tires or vehicle can safely handle), avoiding road hazards, and inspecting tires for cuts, slashes, and other irregularities are the most important things you can do to avoid tire failure, such as tread separation or blowout and flat tires. These actions, along with other care and maintenance activities, can also:
- Improve vehicle handling
- Help protect you and others from avoidable breakdowns and accidents
- Improve fuel economy
- Increase the life of your tires
Underinflated tires are unsafe to drive on. Under inflation causes tires to build excessive heat that can damage tires over time and lead to failure. It can also cause poor car handling and increase stopping distances, either of which causes a driver to crash if they are not careful. Underinflated tires wear unevenly, reducing the life of the tire and requiring more frequent tire replacement. Also having lower than recommended tire pressures wastes gas and thus costing you more at the pump.
As cooler weather approaches it is even more important for drivers to check their tire pressures. Tires typically lose one to two PSI for every 10 degree drop in outside air temperature. Check your tire placard for what your tire pressure should be and start a routine of checking your tires once a month so that you do not end up with a tire failing causing you to lose control and being in a motor vehicle accident.
Normally when an automobile part, such as a tire, causes an accident or damage to a vehicle a comprehensive policy would cover damages that resulted from the incident but not necessarily the replacement cost of tire.
A tire blowout would be considered a covered accident typically if the blow out caused your vehicle to be damaged not though if it is just the tire that suffered damage. If it was the latter then it typically would not be considered a covered insurance event. It would also depend upon the terms of your insurance policy and your insurer's internal guidelines.
For help with determining how to check your tire pressure read through the NHTSA Tire Safety Brochure or go to Safecar a website run by the government and has video clips even that can help a motorist understand their vehicle better.