Depends on whether it is made of biscuit or the same as the ones that the car mounts
We should often pay attention to the pressure of the tires of our cars, since they are the mainstay of the safety of our car. We know that good maintenance and an ideal pressure will avoid headaches, but we always forget one that is also part of the conglomerate of your car: the spare wheel. Do you know what pressure to take it to?
It is the great forgotten inside our vehicle and, since it is not used frequently, it loses bars without us noticing it. Live in the dark and free of weight, without having to support the heavy kilos of the car… But we must bear in mind that a puncture can come at the most inopportune moment, so it is advisable to carry the replacement tire in good condition.
The fifth wheel can be a biscuit type (limited to 80 km/h) or the same as those mounted on the car. Manufacturers often use the biscuit to save space in the trunk and logically reduce costs. As a general rule, they usually have a lot more pressure. Between double and triple a normal wheel.
Generally it usually has 4 bars or even more. To find out how long yours has been, look on the outside of the tire or on the sticker on the car where the normal tire pressure comes from. There also usually comes the value for the cookie wheel.
It is very common for it to be indicated in kPa or PSI. If the inflation pump you use has another average, such as bars, these are the equivalents: 1 kPa = 0.01 Bar. In the example of the photo below: 420 kPa = 4.2 bar; 1 PSI = 0.069 Bar. Real example: 60 PSI = 4.2 bar (rounding).
If your spare wheel is the same as the ones you usually have mounted, it is advisable to inflate the replacement tire to the same pressure as the others, as recommended by the manufacturer. If the values for the two axes are different, for the fifth wheel we will take the maximum value.
Car’s own tire pressure
According to RACE, there is no single pressure for all cars. Each brand offers a different tire pressure recommendation. There is no general norm, although it can be stated that if a tire has a pressure between 2 and 2.5 bars, it will be within a normal inflation range.
To know the correct pressure that your tires should have, each car has a reference sticker indicating the pressures recommended by the manufacturer, whether a single person is traveling or the car is fully loaded. That sticker is usually on the driver’s door, although you can also find it on the fuel filler cap.
If you can’t find the sticker, you can always go to the vehicle manual, where the tire pressures are also indicated.
