Guides · How to Check Tire Pressure
Underinflated Tires
A low tire runs hot and wears the edges. Inflate to the label and inspect if it falls again.
Short answer
An underinflated tire is below the door-label cold PSI. It flexes more, runs hotter, and wears the outer shoulders. Fill it. If the same tire is low again, inspect for a leak.
NHTSA and tire makers have long treated underinflation as a common, preventable failure mode. You will not always see it. The car may just feel vague or use more fuel.
A TPMS light is a late warning on many cars. Monthly checks catch the slow losses that never trip the lamp. One tire that is repeatedly low is not 'just winter' unless the other three moved the same amount.
Do not drive a long highway stretch on a tire you already know is well below the label. Heat builds in the sidewall. That is how a slow leak becomes a sudden failure.
Step-by-step
- 1Measure all tires cold.
- 2Inflate each low tire to the door-label number.
- 3Look at the shoulders and sidewall while you are there.
- 4Write down a tire that needed a large fill.
- 5Inspect that tire if it is low again.
Common mistakes
Adding a little and leaving Finish at the label, then recheck.
Driving on it because the light is not on The light can lag.
Filling only the tire you can see from the driveway Check the inside rears.
Safety notes
A tire sitting on the rim or showing cord is not an inflate-and-go job.
FAQ
How low is dangerous? There is no cute threshold. The farther below the label, the worse the heat and handling. Flat is a stop.
Can I finish a short trip? If the tire is only a little low and looks intact, inflate at the next safe stop. If it looks collapsed, do not.