The rule of thumb that I follow is that the tire's pressure increases by one psi for every ten degrees F. As was said, the mfg's do take temperatures into consideration when building the tire. I always try to check my tires in the morning just after I read all my newspapers. Air temps here rarely get into the extremes, because why? Because its S. CA.
Outside of a dog, a book is man's best friend. Inside a dog, its too dark to read. Mark Twain.
MOTHER SHIP Winnebago View 24H (2007 Dodge Sprinter 3500 Chassis, 2008 Body)3.0 L M-B Diesel V6 bought used with 24K miles. Toad: ROCKY the Flying Squirrel.