Tire air pressure


Years ago when car companies were telling us to run 26 or 28psi in our tires many people said to look at the sidewall of the tire and run the max pressure which was usually 35psi. Now my 225x50x17 tires say the max pressure is 44psi. The Maxima’s sticker says 32. What pressure is best?


Use the pressure rating on the tire.



You ask “What pressure is best?”.

You will get a variety of replies on this since the word “best” is relative. Do you want the smoothest ride, best fuel mileage, most responsive handling, longest tire life, etc?


I want the highest air pressure without loosing traction or causing excessive were on the front end.


Use the pressure rating on the car’s label. Do NOT inflate to maximum pressure. Your car says 32 psi, so inflate to 32 psi. Many drivers prefer to go 2 psi higher than recommended for slightly better mpg.


So when would a peson put in the maximun allowably pressure? If you mostly carry 4 people and a full trunk?? Or towing a trailor?


Never. Use what the manufacturer recommends unless you are overloading the car. The tire recommended pressure assumes your vehicle is fully loaded in capacity and balances ride comfort, tire wear, and fuel economy.

Running max pressure is not advisable.


I posted this question about this issue last week on this forum check recent postings for more opinions. One person responded that any mechanic that set air pressure at the value from the side of the tire was ignorant.Go ahead and look at previous postings.


Good advice from the other people responding. One other thing to consider is that the tire should be “cold” when inflated to the recommended pressure. As you drive, your tire heats up and the air inside expands which increases the pressure. The maximum pressure on the tire’s sidewall is what the tire can safely hold without coming apart.


The max pressure on the sidewall of the tire is what the tire manufacturer recommends as the safe max pressure. That’s because that tire can be applied to many different kinds of vehicles. So one vehicle manufacturer may recommend that the tire pressure be set at 32 PSI for that vehicle, on a different vehicle the manufacturer may recommend that the tire pressure be set at 40 PSI.

The tire pressure recommended by the vehicle manufacturer was determined through testing as to what gave the tire the best performance as to ride, handling, traction, and tire life. So, inflate the tires to the pressure specified by the manufacturer of the vehicle. Afterall, they did all the testing to determine the optimum tire pressure.