Bad tire pressure (too high or too low) can lead to excessive fuel consumption, uneven tire wear, or even a tire burst. To prevent this, it is important to ensure the correct pressure in your tires, which should be checked monthly to get the most out of it.
Part 1 of 2: check the tire pressure
Step 1. Look at the recommended pressures in the builder's manual
You can also check inside the door on the driver's side to see what the standard recommended inflation pressure is for cold tires. This number is the minimum tire pressure recommended by the manufacturer or constructor. Below, you will see under what circumstances it may be necessary to exceed these limits.
- For sedans, vans or even small pickups, manufacturers generally recommend pressures between 1.80 and 2.20 bars, up to 2.75 bars.
- For heavier vehicles (trucks, large pickups, etc.), we have pressures around 3 bars.
- On certain cars, the pressure of the front tires may be different from that of the rear tires.
Step 2. Unscrew the tire valve cap
The valve is a small flexible extension (2-3 cm long) that comes out of the rim. It's messy!
Step 3. Push the pressure gauge onto the valve and read the resulting pressure
If there is a small hissing sound, the gauge is not pushed in far enough and will give you a false reading. It may be necessary to change the angle of the gauge.
With a digital pressure gauge, you may have to press a button to read the pressure. On a mechanical manometer, the reading is instantaneous
Step 4. Put the cap back on the valve
It is not the one that retains the air inside the tire, but it prevents dirt and moisture from the mechanism from entering the valve, which retains the air. Before screwing it back on, put a little saliva to ensure the seal.
In order for the pressure to be correct, you must obtain a figure on the pressure gauge identical to that given in the user manual. If not, adjust the pressure on all 4 tires to get the correct result
Part 2 of 2: Some considerations on the pressure-performance ratio
Step 1. The pressures recommended by the manufacturers are pressures for standard use (a little town, a little highway, etc.)
They do not mean that you will get the most out of your vehicle, you will only be (and this is the most important!) Safe on all types of roads, conditions and handling. Some knowledgeable drivers increase their tire pressure for better performance. For the average driver, more pressure in the tires translates into a more “tapered” vehicle, you can feel all the bumps in the road.
Never over-inflate your tires, as you will lose grip and your braking distances will increase, especially if your 4 tires do not have the same pressure
Step 2. Let's shatter the myth of maximum pressure given by manufacturers
There is a legend that if you exceed the recommended pressure, you expose yourself to the explosion of the tire or to whatever malfunction of the car. The maximum recommended pressure is simply the pressure of the fully loaded tires.
Be aware, however, that if you overinflate your tires, you might run into a few problems if, for example, you take a nice pothole at really high speed
Step 3. If you need to charge your car, increase the pressure
If you have to make a long drive and load your vehicle a lot or if you are hitching a trailer, consider overinflating your rear tires to 0.3 bar. The day after this course, check the pressure and bring it up to standard.
Step 4. Check the pressure when it's cold
Cold reduces the air pressure in the tires, heat increases it. It is therefore important to check the tire pressure at each change of season.
Step 5. Don't judge a tire pressure on the surface
If sometimes we see that the tire is indeed underinflated, it is very difficult to see the difference between a tire inflated to 2 bars and one to 1.5 bars. Don't be fooled by the shape of the sidewalls, for example. Sometimes on radial tires you have sidewalls that seem underinflated, but they aren't, they're designed that way. Do not inflate them too much!
- Tire pressure should not be easily estimated, especially radial tires. Always use a pressure tester.
- By properly inflating your tires, you will save fuel and have a firmer, safer ride. However, do not exceed the maximum pressure indicated on the sidewall of the tire. Test the car to see if you have a good driving feel.
- The standard pressure shown on the sidewall of the tire is given as the maximum pressure, when cold, with the maximum allowable load for the vehicle.
- Increase your tire pressure if you need to load the car or if you have to drive for a long time on the highway.
- The sun's rays heat the tires even if you haven't been driving. And the sun doesn't shine on just one side!
- If you have to drive to the inflation station, note the pressure before you set off. There, it is necessary to over-inflate, generally 0, 20 bar. For example, if you want to inflate your tires to 2, 40 bars and when cold, they are at 2 bars. The tires are therefore under-inflated by 0.40 bar. So once at the station you add the missing pressure back in and now you read 2.40 bar. This is insufficient, because you have driven: you must therefore go up to 2.60 bars. When cold, this will be equivalent to 2.40 bars.
- If your vehicle is heavily loaded or if you are driving fast (at over 130 km / h), slightly increase the pressure in your tires.
- An over-inflated tire (pressure greater than the recommended pressure) leads to a harder ride and you may be in trouble in the event of potholes or collisions with objects lying on the road.
- Beware of tire inflation station pressure gauges. The pipes and fittings may have been abused (impact against concrete, tight coils, etc.) and may not be properly calibrated. It is best to inflate your tire above the recommended pressure, using the pressure gauge on the pump, but once the inflation process is complete, check your tires using your own pressure gauge.
- An under-inflated tire puts more strain on the sidewalls of the tires, increasing stopping distances, increasing fuel consumption and reducing tire life. In rare cases, the tire can burst from excessive heat and you can even go off-road when maneuvering to straighten your vehicle.