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Car Tire Pressure: What’s the right pressure?
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Car Tire Pressure: What’s the right pressure?

Do you have to fill the air in your tire, but you have no idea how much pressure you should have? In this guide, I will talk about all the aspects and you will be an expert in car tire pressure!
I am Magnus and I have been working as an automotive technician for a long time. I get this question a lot of times and that is why I decided to write this article.

The easiest way to find the right tire pressure you should have is to check in your service owners manual. Inside the service manual book, there is often information of where to find the tire pressure label. The most common place is on the chassis, behind the driver door and sometimes at the location of the spare tire. It will look something like this:

car tire pressure label

You may be looking at that label and don’t understand anything at all, but don’t worry I will explain it all to you. The first thing you have to check is what size you have on your tires. Because on the most labels, there are many different tire sizes. You will find anything like 195/65 – 16, that’s the size of your tire.
When you know what tire size you have you can just check the label.

What do cold tire inflation pressure mean?

They are writing the cold tire inflation pressure because that is the pressure you should have when the tires are cold. But why does it matter? You may ask. Checking the air pressure when the tire is cold vs warm could be a big difference

Cold tire – Lower Pressure

Hot tire – Higher pressure

How much the difference depends on the tire size etc, but the difference could be around 0.4 bar ( 6 psi ~ ).

How can I check the tire pressure myself?

You can either check your pressure with a tool at home or drive to a shop that will check it for you. If you want to check it yourself sometimes you can get a tool like TEKTON 5941 Digital Tire Gauge, 100 PSI Link to Amazon. It’s not expensive at all and can be really good to check your tire pressure with periodically to make sure that you are not driving around with too low pressure.
If you want to fill your tire you should use compressed air. You can find one at a workshop or probably at your local gas station.

My label has different tire pressure depending on how many passengers and load?

Yes, the most labels have different pressures depending on how much load you are going to have in the vehicle.

High load/weight – Higher Pressure
Low load/weight – Lower pressure

car tire pressure

What’s better, Over or Under the recommended pressure?

I always recommend driving a bit over the recommended pressure. In older tires the was worn out in the middle of the tire thread if you were driving too much pressure, but with newer tires, I don’t see that happen if you don’t drive with an extremely high pressure. Around 0.1-0.3 bar ( 1-4 psi ) over is no problem.

In fact, I have seen in several newer vehicles with a tire pressure warning that if you read for an example 2.5 bar ( 36 psi ) and you try that. It will still give you a warning message because the tire pressure should be OVER that value. So what’s happening if you fill it with 2.6 bar ( 38 psi ) when the tire is warm? Yes, the warning light will come back when the tires are cold.
So in general always add 0.1-0.2 ( 1-3 psi) more pressure than the label is telling you.



My car is not using the original size of the tires, how much pressure should I have?

Either you can ask the one who sold the tires or you can check this list for a general tire pressure chart.  I don’t recommend it, your car can wear out the tires faster and you can get less control over the car. But it is a good benchmark to know roughly what tire pressure you should have. Remeber what I told you before, it’s often better to have a bit more of pressure than having too low pressure.

  • Small Sized car normal tire size ( around 185/55 – 15 ) ~ 2.1 bar  ( 30 psi)
  • Medium Sized Car normal tire size ( around 195/55 – 16 ) ~ 2.5 bar ( 36 psi)
  • Big Sized car normal tire size( around 265/45 – 18 ) 2.9 bar ( 42 psi ).

In general, if you have bigger rims with a lesser tire profile you should use higher pressure.

car tire pressure

Some additional information

You should never drive around with too low pressure, you will damage your tire and probably the rim. Your car will also require more fuel because it won’t roll as easy as with the right pressure. It’s also dangerous because you will have a lot less control of the car at higher speeds. It’s always better to have a bit higher pressure. Lesser pressure can be good if you are looking for more grip at lower speeds.

I hope you like this short guide if you have any more questions that didn’t get answered you can contact us or Ask a question.
Let me know if you like this guide by leaving a comment below. If you want us to add or change anything, let us know! See you in the next article!

If you want to watch a video in addition to this article, then I can recommend this video:

 

 

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