You can safely inflate your tires, in most cases, to a higher pressure. For example, my minivan manual says to inflate to 35psi, but the max pressure on the tire sidewall is 44 psi. I find I can run at 40psi without making the ride too harsh, and I've picked up a couple of MPG. Your mileage (and comfort level) may vary. Never exceed the cold inflation pressure embossed on your tire sidewall.
by b3n on August 23 2008
this tip works for 60% of voting Fuelly members.