Keeping tires properly inflated seems obvious, but it is often easily overlooked. Tires lose about 1 psi of air every month, which has a big impact on safety but also the range of an electric vehicle. Plus, the extra weight of an EV is harder on tires, making it even more important to ensure that your tires have enough air.
Underinflation, the most common problem, reduces tread life by increasing tire wear on the outer edges or shoulder of the tire. Too little air in tires also generates excessive heat, which reduces a tire’s durability and the range of an electric vehicle.
And then there’s rolling resistance. Driving an electric vehicle on underinflated, soft tires means your car has to work more. And with an EV, that means drawing more from the battery and draining its range. Underinflated tires can also greatly impact your car’s handling and how it responds. Steering is less precise and low air pressure makes it harder to navigate tight turns or maneuver quickly. Low tire pressure also increases braking distance and weakens vehicle traction.
Sometimes the problem is overinflation, which can happen just after you fill the tire but went over the recommended air pressure. In this case, the center of the tire tread is where the wheel will meet the ground and end up bearing most of the weight. Such conditions will quickly wear out the center faster than the outside edges so that replacement tires are needed sooner rather than later. Overinflation can also negatively impact noise and comfort. To find the proper air pressure, consult your electric vehicle’s owner’s manual or find the recommended air pressure on the sticker on your car’s door jamb.
Since tire pressure really affects your drive and the all-important range of an electric vehicle, it is a good idea for EV owners to check the air pressure once a month when the tires are cold or at least three hours after a drive. Keep in mind that tire pressure also changes with the outside temperature and will measure lower during a deep freeze or cold winter weather.
Most electric vehicles are equipped with a Tire Pressure Monitoring System (TPMS), which alerts you when there is a big change in your vehicle’s tire pressure. As helpful as these systems are, the indicator light only activates when the air pressure is very low, and there is no replacement for manually checking that your tires are properly inflated.
