I do not intend this thread to become another discussion about the merits, safety and benefits of inflating tires to sidewall rating or not.
With that out of the way, I just wanted to say that if the area in which you live has seen a 20 degree drop in temperatures, that unless you've inflated your tires within the time frame of the temperature drop, that it's time to inflate your tires. Furthermore, I'd like to stress checking your tire pressure before driving on them is critically important. Check your tire pressure once before driving off (early morning before work) and right before you go to inflate your tires that day; then while inflating, subtract the difference in tire pressure. Whether you inflate your tires to sidewall rating, above, to what the manufacturer recommends or anywhere in between, it doesn't matter, just inflate them!
All tire pressure guidelines are ALWAYS when the tires are COLD, soon as you drive on those tires, even for a 1/4 mile, those tires are no longer cold and the PSI of the tire can rise by several points!!!
With that out of the way, I just wanted to say that if the area in which you live has seen a 20 degree drop in temperatures, that unless you've inflated your tires within the time frame of the temperature drop, that it's time to inflate your tires. Furthermore, I'd like to stress checking your tire pressure before driving on them is critically important. Check your tire pressure once before driving off (early morning before work) and right before you go to inflate your tires that day; then while inflating, subtract the difference in tire pressure. Whether you inflate your tires to sidewall rating, above, to what the manufacturer recommends or anywhere in between, it doesn't matter, just inflate them!
All tire pressure guidelines are ALWAYS when the tires are COLD, soon as you drive on those tires, even for a 1/4 mile, those tires are no longer cold and the PSI of the tire can rise by several points!!!