Mini Bio (1). Jo Ann Pflug was born on May 2, 1940 in Atlanta, Georgia, USA. She is an actress, known for MASH (1970), The Night Strangler (1973) and The Fall Guy (1981). She was previously married to Chuck Woolery.
Current trend is to use Nitrogen inside the tires. More dense than regular air so pressures are more stable. But if you check your tires often you will be ok with good old fashioned air. The Tire plackard on the door jamb (some times under the console lid) is cold tire pressure. So add 3 or 4 psi after you drive and the tires warm up. Also there is a owners hand book section 8 page 39 all the way to page 50 continues to tell you about tire grades and DOT numbers and general information about tires. Depending on your car tires size Altima's use 29 to 35 psi cold pressures.
Tires are given a maximum load rating based on the tire's size, construction and inflation pressure. P-metric sized tires--tires with sizes starting with a P such as P235/75R15--are given a load range rating of either SL or XL. SL stands for Standard Load and XL indicates extra load. An SL-rated tire has its maximum load capacity at an inflation pressure of 35 psi. XL tires can carry a heavier load when inflated to 41 psi.