Driving on 20 PSI is generally unsafe and not recommended. Most passenger cars require a tire pressure between 30-35 PSI (pounds per square inch). At 20 PSI, the tire is severely underinflated, which can lead to excessive heat buildup, poor handling, reduced fuel efficiency, and a significantly increased risk of a blowout. You should inflate your tires to the manufacturer's recommended pressure immediately.
Severe underinflation causes the tire's sidewalls to flex beyond their design limits. This flexing generates excessive heat, which can degrade the tire's internal structure and lead to a sudden failure. Your vehicle's handling will feel sloppy, with slower steering response and a higher risk of losing control during emergency maneuvers. Furthermore, the increased rolling resistance means your engine has to work harder, directly lowering your miles per gallon (MPG).
The correct PSI is not the number on the tire's sidewall; that's the maximum pressure. You'll find the recommended pressure for your specific vehicle on a sticker inside the driver's door jamb or in the owner's manual. If you find yourself at 20 PSI, it's crucial to check for punctures. Add air as soon as possible, and if the tire won't hold pressure, seek professional repair.
| Vehicle Type | Typical Recommended PSI Range | Risk Level at 20 PSI |
|---|
| Sedan / Compact Car | 32-35 PSI | Severe |
| SUV / Crossover | 33-36 PSI | Severe |
| Light Truck / Pickup | 35-40 PSI (rear may be higher) | Severe |
| Minivan | 35-38 PSI | Severe |
| Performance Car | 38-45 PSI | Severe |
