Finding that low tire pressure warning light illuminating on your dashboard can be worrisome. While it may be tempting to ignore it and continue driving, driving any significant distance with low tire pressure is extremely hazardous.
This article will cover everything you need to know about driving with low tire pressure – the risks, how to do it safely in an emergency, tips to minimize damage, how long you can drive, and how to properly re-inflate your tires.
Here’s a quick answer: You should not drive with low tire pressure except in emergencies. If unavoidable, drive less than 50 miles and 1 hour maximum. Go under 50 mph, remove extra weight, and stay in the right lane. 20 PSI is absolute minimum to drive – inflate ASAP. The lower the pressure, the less distance and slower you should drive before re-inflating tires to recommended PSI.
Dangers of Driving with Low Tire Pressure
Low tire pressure, also called underinflation, can happen gradually over time as air leaks out or suddenly due to a puncture. Either way, it negatively impacts your vehicle’s handling, braking distance, gas mileage, and tire lifespan. More importantly, it significantly increases your risk of a blowout.
Here are some of the main risks of driving with underinflated tires:
- Blowouts – Low pressure causes excess heat buildup in the tire which can lead to sudden catastrophic failure at high speeds. This is extremely hazardous if it happens on the highway.
- Poor handling – Underinflated tires lose traction, are less responsive, and make your vehicle harder to control especially when turning or braking. This increases accident risk.
- Longer braking distance – Low pressure decreases the tire’s grip on the road resulting in longer stopping distances which can lead to collisions.
- Lower gas mileage – Due to increased rolling resistance, underinflated tires reduce fuel economy by up to 10%.
- Reduced tire life – Heat and flexing damage from low pressure wears out tires much faster. Significant underinflation can reduce tire lifespan by thousands of miles.
Given these considerable safety and longevity risks, you should avoid driving with low pressure except in emergencies.
What is Considered Low Tire Pressure?
Tire pressure is measured in PSI (pounds per square inch). The specific recommended inflation level varies by vehicle make, model, tire size, and load weight – consult your owner’s manual.
In general, here are the guidelines:
- Ideal pressure – Around 32-35 PSI for most passenger vehicles.
- Low pressure – Under 30 PSI should be considered low.
- Too low – 20 PSI and below is extremely dangerous to drive any distance.
Anytime the tire pressure is 10% or more below the recommended level, it should be addressed immediately. Driving at high speeds with significantly underinflated tires risks sudden blowouts and accidents.
How Low Can Tire Pressure Be Before Driving is Unsafe?
As mentioned above, you should avoid driving at all with pressure lower than 20 PSI, except in extreme emergencies. 20 PSI is the absolute minimum required to safely drive a very short distance at low speeds to get the tire re-inflated or replaced.
Here are the guidelines based on tire pressure:
|20 PSI and below
|Do not drive except if absolutely necessary in an emergency. Drive less than 10 miles max to get repaired.
|Drive only if urgent and minimize distance – ideally less than 20 miles at under 50 mph.
|Try to get repaired ASAP. OK for short trips under 50 miles if needed.
|Within acceptable range for most vehicles but top off to recommended PSI.
Remember – the lower the pressure, the shorter distance you should drive before getting it fixed. Anything below 20 PSI is extremely hazardous.
How Long Can You Drive on Low Tire Pressure?
When driving with low tire pressure is unavoidable, follow these guidelines for maximum drive time and distance based on conditions:
On paved roads (ideal conditions):
- No more than 50 miles
- Less than 1 hour
- Less than 10 miles
- Under 10 minutes
- Less than 40 miles
- Under 30 minutes
- Less than 30 minutes
- Drive slowly to avoid overheating tire
The bottom line is you should minimize distance and time driven with low pressure. Drive only if absolutely necessary, stay under 50 mph, and get your tires properly inflated as soon as possible.
How Fast Can You Safely Drive with Low Tire Pressure?
When driving any distance is unavoidable on low tire pressure, follow these speed recommendations:
- 20 PSI or below – Do not exceed 10 MPH except in extreme emergency. Crawl to get repaired ASAP.
- 21-30 PSI – Maximum 50 MPH, slower is safer. Stay in right lane.
- 31-35 PSI – OK up to highway speeds but get repaired soon.
Excessive speed compounds the risk of overheating and sudden blowouts from underinflated tires. It’s critical to keep your speed low when you have no choice but to drive with low pressure.
Tips for Driving Safely on Low Tire Pressure
If you must drive a short distance before you can properly re-inflate your tires, keep these precautions in mind:
- Maintain a maximum speed of 50 MPH or slower
- Remove any extra weight from inside the vehicle
- Keep your hazard lights on
- Stay in the right lane at all times
- Avoid sudden braking or sharp turns
- Open windows to monitor for any noises indicating further tire damage
- Be prepared to pull over immediately if tire damage worsens
- Park safely and call for assistance if driving becomes unsafe
Though inconvenient, taking these extra steps can prevent a dangerous roadside breakdown or accident.
Consequences of Regularly Driving on Low Tire Pressure
Many drivers underestimate the cumulative damage from repeatedly driving on under-inflated tires over time. Here are some of the potential consequences:
- Premature tire replacement – Constant underinflation wears tires out much faster by causing uneven and excessive tread wear. This can shorten the lifespan by thousands of miles.
- Decreased braking ability – Driving daily on low pressure gradually reduces braking effectiveness and increases stopping distance. This makes it harder to brake quickly in an emergency.
- Steering issues – Tires worn from chronic low pressure lose traction and are harder to control, especially for emergency maneuvering.
- Higher repair costs – In addition to paying for frequent new tires, alignments and other maintenance are needed more often.
- Lower fuel economy – A consistent 10% drop in MPG from underinflation adds up to hundreds of dollars per year in wasted gas.
Routinely checking and maintaining proper tire pressure saves money in the long run and prevents safety risks.
Is it Illegal to Drive with Low Pressure or a Flat Tire?
Most states prohibit driving with severely underinflated or flat tires because it poses a significant traffic hazard. Specifically:
- Driving on tires with less than 20 PSI is illegal in most states.
- Operating a vehicle with a fully flat or damaged tire is against the law everywhere.
- If a law enforcement officer judges your low tires to be a danger, you can be ticketed and fined in any state.
Before hitting the road, do a quick walk-around inspection and use a pressure gauge to check inflation levels. It takes minutes and avoids legal issues and safety risks.
How to Properly Re-Inflate Low Tires
DIY tire inflation is quick and easy with some basic steps:
- Remove tire valve cap and connect air hose firmly over stem
- Check recommended PSI on door jamb or owner’s manual
- Inflate to recommended pressure level (not the max pressure on tire sidewall)
- Use a high quality pressure gauge for accuracy
- Re-check pressure with gauge and add more air if needed
- Replace valve cap when finished to prevent leaks
Many gas stations have free air pumps for tire inflation. There are also convenient portable compressors that plug into your car’s 12V outlet for roadside emergencies.
Maintaining proper inflation by frequently checking tire pressures can prevent the headaches of low pressure driving risks and consequences. But if you do end up with an underinflated tire, limit your driving, go slow, and get it re-inflated immediately.
Frequently Asked Questions about Driving with Low Tire Pressure
Is it OK to drive with a slow leak in a tire?
No, you should get even a slow leak repaired as soon as possible. A slow leak will gradually lower inflation and tire pressure may become dangerously low on a longer drive.
How far can you drive if a tire is completely flat?
You should not drive at all on a fully flat tire except to limp to a safe pullover spot if you’re already moving. Driving any real distance risks damaging the wheel and creates a hazardous condition. Call for assistance.
What if I don’t have a tire pressure gauge?
Stop by any auto parts store or gas station and buy an inexpensive dial or digital pressure gauge. Checking pressures regularly without a gauge is guessing and could lead to significant underinflation over time.
What PSI is too low to add air – do I need a new tire?
As long as the tire is not visibly damaged, any PSI level can safely be re-inflated. Even at 5-10 PSI, adding air will reinflate the tire. Only if it has major damage would it need replacement instead.
What are signs I may have a slow air leak in a tire?
Some indicators of a slow leak requiring repair include having to refill a specific tire more often than the others, a tire losing more than 2 PSI per month when checked, or hearing air hissing from the valve stem or tread area.
Driving any distance with severely underinflated tires is risky. Follow these guidelines on safe driving limits, proper inflation, and leak repairs to avoid blowouts or losing control behind the wheel. Stay safe out there!