2009 Toyota 4Runner Owners Manual - Page 418

4-3. Do-it-yourself maintenance If the tire inflation pressure is not within the recommended levels, adjust inflate the tire. If you add too much air, press the center of the valve to lower. After completing the tire inflation pressure measurement and adjustment, apply soapy water to the valve and check for leakage. Reinstall the tire valve cap. n Tire inflation pressure check interval You should check tire pressure every two weeks, or at least once a month. Do not forget to check the spare. n Effects of incorrect tire inflation pressure Driving with incorrect tire inflation pressure may result in the following: l Reduced fuel efficiency l Reduced driving comfort and tire life l Reduced safety l Damage to the drive train If a tire needs frequent refilling, have it checked by your Toyota dealer. n Instructions for checking tire inflation pressure When checking tire inflation pressure, observe the following: l Check only when the tires are cold. If your vehicle has been parked for at least 3 hours and has not been driven for more than 1 mile or 1.5 km, you will get an accurate cold tire inflation pressure reading. l Always use a tire pressure gauge. The appearance of the tire can be misleading. In addition, tire inflation pressures that are even just a few pounds off can degrade ride and handling. 396