Like bicycles, motor vehicle tires require a certain air pressure to perform optimally. Without it, driving on them can be dangerous.
This post answers your questions about driving with low tire pressure. We explore how long you can drive with low tire pressure, how low is too low for tire pressure, and the lowest tire pressure you can drive on. You’ll then better understand how tire pressure affects your fleet.
Understanding Low Tire Pressure
Low tire pressure occurs when the outward force of air in your vehicle’s tires is below the manufacturer’s specifications. Tire pressure in automobiles varies from one model to another. However, most vans need pounds per square inch (PSI) readings between 28 and 35.
You can measure tire PSI by connecting Schrader valve nozzles to pressure gauges (either on pumps or standalone units). Digital systems offer the most accurate readings, but conventional dials are also helpful.
Is It Safe to Drive with Low Tire Pressure?
No, it is not safe to drive with low tire pressure. Under-inflating tires can lead to numerous issues affecting driver safety.
Is it risky to drive with low tire pressure? Unfortunately, the answer is “yes.” Problems include reduced vehicle control and handling, higher likelihood of blowouts, longer stopping distances, and additional tire wear.
Effects of Driving with Low Tire Pressure
The effects of driving with low tire pressure can vary depending on the extent of the flatness and vehicle type. Heavy vans and trucks may experience more severe effects from deviating from the manufacturer’s specifications than smaller autos.
Increased Stopping Distance
For example, driving with low tire pressures affects how onboard electronic emergency braking systems respond to tire sensor feedback. Unreliable data can prevent them from working correctly, increasing stopping distances.
Premature Wear
Driving with low tire pressures also leads to premature and uneven wear. Slightly flat tires may not line up flush with the road surface or bulges may create points of pressure that destroy the tread on the inside and outside of the wheel.
Severely flat tires may also damage the structure of the tire rubber itself as it bends and contorts under the vehicle. This process can lead to tears, flats, and tire write-offs (even if new).
Poor Handling
Poor handling is another problem with low-pressure tires. Flexing tires makes steering less responsive to drivers’ inputs, causing the vehicle to track unreliably.
More Blowouts
Finally, low tire pressures can lead to more blowouts. The greater contact area with the road causes increased friction and tire damage.
How Low is Too Low for Tire Pressure?
Most fleet vehicles need tires inflated to between 32 and 35 PSI. However, the actual number will vary depending on the tires’ volume and the vehicle’s weight (when loaded and empty).
Manufacturers often provide detailed information on optimal pressure scenarios, helping you determine the inflation level by vehicle or trip. If you aren’t sure how much to inflate your tires, check the pressure rating on the sticker inside the driver’s door jamb. It should provide information on safe inflation levels.
Pressures below 20 PSI are considered “flat” and dangerous to drive on. Usually, low pressures indicate a puncture but can also occur over long periods naturally as air escapes.
The Dangers of Low Tire Pressure
The physical dangers of low tire pressure are considerable. These include a heightened risk of driver injuries, collisions, and damaging property during accidents.
However, there are also many financial ramifications. For example:
- Your insurer might raise your fleet’s premiums if they discover a low-pressure-related blowout caused the accident
- The efficiency of your vans, trucks, and other rolling stock might decline, making your enterprise less competitive
- You may have costly bills replacing worn or blown-out tires every few weeks or months
How Long Can You Drive with Low Tire Pressure?
You shouldn’t drive on low tire pressures if you can avoid it. It may void your insurance and increase the risk of vehicular damage and accidents.
If a low tire pressure warning light appears on your dashboard, pull over and check your tires (preferably with a reliable pressure gauge). Testing by the roadside tells you whether you have a mechanical problem or a sensor issue.
If the pressure is above 20 PSI, drive the vehicle slowly to the nearest garage that has a pump, or re-inflate the tire by the side of the road if you carry your own.
How to Identify and Handle Low Tire Pressure
The best way to handle low tire pressure is to take your vehicle to a garage for an assessment. Mechanics will disassemble the wheel and look for evidence of intrusion on the rubber. Sometimes they will find nails, wires, and other foreign objects inside the tire, while other times they may notice problems with the wheel’s surface, allowing air to escape.
If you aren’t sure whether your tire is low pressure, look for the following signs:
- A bulge where the tire meets the ground (ideally, the tire’s sidewall should be firm and round, not compressed-looking)
- Uneven tire wear on the treads (low pressure can cause wear to accelerate on one side compared to the other)
- Changes in handling (you may notice the car feels less stable at speed, turning, or under braking)
- Lower fuel efficiency (the vehicle may require additional energy to overcome the added friction from the under-inflated tire)
Ideally, you should check tire pressures regularly alongside alerts from tire pressure monitoring systems (TPMS). Old sensors aren’t always accurate in older vehicles, potentially missing pressure issues.
Now You Know When Tire Pressure Is Too Low
In summary, tire pressures are too low when they fall out of the manufacturers’ specified range. Lower PSIs can occur because of punctures, wheel issues, and lack of regular maintenance.
We suggest checking tire pressures every two to three weeks or so. It is also worth watching out for the signs of low tire pressure to keep fleet drivers safe.
