On our first (2016) road trip FL to AK we were running 120 psi (max rated pressure for our tires) IT WAS AWFUL! After sifting though the tire manufacturers load chart as BW explained. We ended up with 90 psi on the front & 75 psi on the rear duals. The ride difference was like night & day.
What a revelation! Thanks Dan. For some dumb reason I had been setting the same tire pressure for all my tires. The light just went on that the rears and fronts are going to run different pressures. Kicking myself
Pure and simple-weigh your bus then run what is recommended in the tire inflation tables for your tire size. DO NOT run the maximum tire pressure imprinted on the tire-all you'll get is bus that rides like a fork lift, tire wear in the middle of the tire, and the tire not fully seated on the pavement. With the proper tire pressure, you'll have a nice riding bus, tires wearing well, and the maximum tire pattern on the pavement for maximum traction. Good Luck, TomC
School buses and transit authorities all run their tires about 10PSI below max ,there no way in hell will I run a 315/80/22.5 $700.00 Michelin tire at 75 psi.I have a SilverLeaf monitoring inside the tire every 10 psi I add to the Michelins will drop the temperature about 10 degrees I found that out bringing it home from Texas when I thought the tires where to hot to touch with 80 psi .Every time I blow a Michelin tire the 1st they say was to low of air pressure
Geezus... we aren't loading our buses.We don't usually need the air pressure that a loaded bus needs.All the commercial tire guys know is loaded heavy, they don't know what to do with us.