Originally Posted by
EAD15
Max pressure is just that, the maximum pressure the tire was designed for. You would only ever fill the tire to the max pressure if you were loading that tire to it's maximum designed load. If you were to try and max out the tire load in an Aveo, I think your suspension would have a few words for you first...
Remember, as you increase the pressure in the tire, less of the tire is in contact with the ground. This reduces braking effectiveness, reduces your drag, and increases MPG. The reverse is true as you lower tire pressure.
The manufacturer is going to recommend a tire pressure that provides effective braking, adequate tire life, and acceptable fuel economy. Of course, those numbers assume you stay with the suggested tire sizes. Change the tire size out of spec and you are on your own to figure that out