What should the tire pressure be on my car?

Question posted by Janet W. regarding her Lexus RX350.

We are headed to tahoe for summer break and want to make sure our tires are properly inflated.  Can you tell us the easiest way to find out what is the recommended tire pressure is on our vehicle?

Often times we get the question, what is my vehicles recommended tire pressure? The truth is that all cars require different tire pressure but we will give you the general rules below.

What should the tire pressure be on my car?

Where do I find the recommended tire pressure for my vehicle?

Most vehicle manufacturers require a tire pressure of 32psi to 36psi on cars, SUVs, and light trucks. If you want to find the exact tire pressure for your car, check the following places:

  • Sticker/decal in the glove box
  • Vehicle owners manual
  • Sticker/Decal in the driver inner door edge/door jam
  • Sticker/Decal in the passenger inner door edge/door jam
  • Sticker/Decal inside the fuel door

The sticker/decal that indicates manufacturer recommended tire pressure settings will typically look like the one below.  If you have the capability to tow with your vehicle it may also have a different set of specifications for these driving conditions.

How much air should I put in my tires?

Where can I check and fill up my tires?

You can fill your tire pressure at most gas stations, independent repair shops, or a service station. Many times at a gas station, the air and water fill up will not be in direct site check with the attendant for the location.  Also, it is worth investing in a reliable tire gauge as many fill stations guages are damaged or non existent.  It is also worth noting that some stations charge you a few quarters to run the air machine so be sure to get change!

How do I fill up my tires to the proper pressure?

Most tire pressure gauges are the same (picture below). Remove the plastic cap on the tire that you want to inflate. Push front of the tire gauge onto the tire valve stem (where you just removed the plastic cap). Squeeze the handle on the tire pressure tool, this will allow air to flow into the tire.  When the handle is released the gauge will display the current pressure.  (Note: if the gauge does not pop up to display the pressure make sure the fill hose/gauge is pushed firmly onto the tire valve stem.)

How do I fill up my tires with air?

Why was my tire low on air?

After you have filled the tires you still have to answer the question, why was the tire pressure low on my car? There are several reasons: nail in the tire causing a leak, leaking valve stem or leaking valve core, air leak from the sidewall of the tire, leak from the bead of the tire (this is where the tire attaches to the metal rim), and even sometime the metal rim itself could have a crack causing a loss in tire pressure.

NOTE:  Temperature and time also effect tire pressure. Every temperature increase of 10 degrees F* will cause an increase of tire pressure of 1psi and the opposite is true for a decrease in temperature. And over time tires do lose air pressure at a very slow rate but if you have your car serviced regularly the mechanic should be checking it.

As always, if you have any further question regarding tire pressure, filling procedures, or anything automotive feel free to contact A+ Japanese Auto Repair Inc.

Eric S.

Auto Mechanic San Carlos - A+ Japanese Auto Repair Blog

A+ Japanese Auto Repair Inc.