Tire flat spots — What causes them?

Learn why not driving for a month or more causes tire flat spots

Tire flat spots are a common issue when your vehicle is parked in one place and not used for a month or more. This is more common if you’ve driven the vehicle, warmed up the tires, and then park it in cold weather. This is caused by the warm nylon cap in the tire cooling down and taking a “set.” Later, when you drive, you’ll feel a thumping from this flat spot. In most cases, the flat spot will warm and resume its normal shape within 20 miles of highway driving.

Which tires are more prone to flat spotting

All tires can develop flat spots, but it is more common on high-performance tires due to their different construction. High-performance tires are softer than other tires and are designed to hang onto the road and corner at very high speeds. They’re more prone to flat spotting because:

• They’re more flexible so they flatten more easily when parked.
• They have wider footprints, so they take on more heat or cold from the road surface
• They have stiffer and shorter sidewalls. So the tread on the bottom of the tire flattens out more on the road.

How to prevent it

The single best way to prevent tire flat spots is to put the vehicle on jack stands when it won’t be used for long periods.

How about over-inflation to prevent flat spotting?

You’ll see all kinds of advice online to over-inflate your tires to the maximum pressure listed on the sidewall. No tire manufacturer recommends inflating normal passenger tires to that pressure. In fact, Tire manufacturers disagree on whether to over-inflate at all when your vehicle will be parked for a month or more. Even when they do recommend over-inflation, it’s to the maximum listed on the sidewall; it’s just 3 psi. The only exception is for high-performance tires. In those cases, most tire makers do recommend inflating to the maximum listed on the sidewall. However, their preference is to put the vehicle on jack stands.

See this post on tire company recommendations for long-term storage.

Some people recommend using tire cradles — do they work?

Nope. To work, the curvature would have

No tire manufacturer recommends tire supports or tire cradles

to match the tires’ curvature exactly. But the cradles are sold in a one-size-fits-all configuration. Not a single tire maker recommends these devices.

©, 2024 Rick Muscoplat