Tires are an important part of your vehicle, and should be checked on a regular basis. If the vehicle is not in use, it can cause tires to flat spot. As the tires rotate, they go from a relaxed state to a loaded state about eight hundred times every mile. This constant deflection generates heat that makes the tires more flexible. But once they are parked, the spot in contact with the ground flattens, as it is pressed against the road’s flat surface as the tires cool. This is what generates flat spots. Until the tires warm up again, the flat spot on each tire can cause a ride disturbance that will be felt for the first few miles the next time the vehicle is driven.
Flat spotting can be temporary, the tire will round out as driving warms it up, or in the most severe cases, permanent. A flat spot’s severity is often a function of the tire size, internal structure, load, ambient temperature and time spent stationary. Low aspect ratio tires have less sidewall flex due to their short sidewalls and much of their load carrying capacity is absorbed by the deflection of their wide footprints. Heavy loads and too little air pressure in the tires will allow them to deflect more where they come into contact with the ground. This allows even more deflection, increasing the severity of the flat spotting. Cold ambient temperatures make rubber compounds stiffer, increasing their tendency to flat spot.
While there is no way to completely avoid temporary tire flat spotting, knowing what to expect under different conditions will help minimize its inconvenience. It is important to check and reset tire inflation pressures to those recommended by the vehicle manufacturer on the vehicle placard or owners manual when taking a vehicle out of storage. Tire flat spotting would be most noticeable when beginning to drive a vehicle that has been stored incorrectly with the weight of the vehicle pressing down through the tires to the ground. When storing a vehicle for more than a few weeks, it is best to drive the vehicle until it is thoroughly warmed up and then immediately put it up on blocks after arriving at the storage location. Doing this takes the load off of the tires completely. Not doing this on a vehicle that will be parked for a few months runs the risk of permanently flat-spotting the tires.