Things to Understand About Determining Car Tire Pressure

When you fill or add pressure to your car tires, it should not be done carelessly or just until the tires feel harder. Car manufacturers usually provide information regarding the standard tire pressure that must be understood for certain types of cars. To find out what the standard is, you can check the information on the tire pressure sticker. This sticker is usually affixed to the B-pillar or the driver's door. Here are the things you need to understand about tire pressure guidelines for cars.

Tire Pressure Based on Car Type

The standard tire pressure below only applies if the size of the rims and tires you are using still conforms to the manufacturer's or original equipment specifications. However, if the tires and rims have been modified or replaced, the following guidelines may no longer apply.

The air pressure for Honda Mobilio tires is 30 psi
The air pressure for Honda Brio tires is 26 to 29 psi
The air pressure for Toyota Avanza tires is 30 to 32 psi
The air pressure for Honda Civic tires is 35 psi
The air pressure for Suzuki Ertiga tires is 29 to 35 psi
The air pressure for Daihatsu Xenia tires is 30 to 32 psi
The air pressure for Toyota Innova tires is 33 psi
The air pressure for Toyota Fortuner tires is 30 to 33 psi

The Influence of Rim Size on Air Pressure

Sometimes people think that the air pressure in tires is also determined by the size of the rims. The rim itself is the dimension size of the tire's wheel and is measured in inches. Therefore, people often think that the tire pressure for 16-inch rims must be higher than for smaller rims like 15-inch rims.

So if the car manual states that the tire pressure for 14-inch rims, which are the standard and original size, is 33 psi for both front and rear, many will then increase the tire pressure to 35 psi and so on. Is this correct?

Actually, the air pressure in tires is not significantly affected by the size of the tires or rims. Therefore, even if the size of the rims and tires is no longer the same as the original equipment, the air pressure does not necessarily change immediately. Air pressure is influenced by at least three factors, namely:

The weight of the car
The distribution of the car's weight
The setup or adjustment of the car's suspension

Therefore, even if the rim size has changed, it does not automatically mean that the air pressure in the tires must be increased. If the standard tire pressure for 16-inch rims from the manufacturer is 33 psi, then just follow the recommended pressure unless the car has to carry additional weight.

The Effect of Additional Load on Tire Air Pressure

As previously explained, the weight of the car affects the air pressure that must be applied to the tires. Therefore, you usually need to add air pressure to the tires if the weight the car is carrying exceeds the standard weight. For example, the standard air pressure allowed is 33 psi for carrying four passengers and light cargo.

If you have to carry up to 7 passengers in one car and also add heavy cargo, you need to increase the pressure in each tire. The increase can usually reach 2 to 3 PSI.

Maximum Load Allowed

To keep the tire pressure from exceeding the maximum load limit allowed, you are strictly prohibited from carrying a load that exceeds the maximum weight allowed. If the weight carried exceeds the recommended limit, it can cause the tires to be excessively pressured, potentially leading to accidents.

To calculate the maximum load allowed, you can check the max weight information on the tire and the curb weight of the car. For example, for a tire with a maximum weight of 220 kg and a curb weight of 150 kg, it means the car can only carry an additional load of up to 700 kg, including passengers and the driver.

Tires Should Be Cold When Inflated

A tip to maintain tire air pressure and keep the tires durable is to inflate them while they are still cold. If the tires are hot from being used on hot roads or parked under direct sunlight, the air pressure measurement may not be accurate. This is because the air inside the tires will expand due to heating.

When air pressure is added while the tires are hot, the recorded pressure may be correct at that moment. However, when the tire temperature decreases and becomes cold, the air pressure will certainly drop. You can use nitrogen gas if you want more stable pressure.

Reasons Why Tire Air Pressure Must Be Correct

Inflating the air pressure must meet the standards and should not be less or more. When the pressure is excessive, it can interfere with braking performance on slippery and wet roads. Tires can even slip if the pressure is too high. For tire pressures exceeding the limit by 5 to 10 psi, there is a risk of explosion. Meanwhile, if the air is below the standard, it risks causing uneven tire wear.

Checking and ensuring that the car tire pressure meets the established standards is very important to guarantee safety while driving. Incorrect tire air pressure can increase the risk of car accidents on the road.