Modern tires have a maximum pressure printed on the side. For longest life, should they be run at the maximum or something less?
Don't run at maximum.
For maximum life AND a comfortable ride, consult your owners manual, the sticker inside the trunk or inside the drivers door for the car manufacturer's recommended pressure. You can go a few PSI higher if you like but don't over do it.
Erik's right. Most modern cars have a sticker in the drivers door jamb that indicates recommended pressure front and rear.
I have always run most of my vehicles at the Max rated psi and get good wear. I hope to get a bit better mpg with the higher pressure due to less rolling resistance.
On our G37S I did not thought because of the rough ride. Probably more important not to run them at too low a pressure.
I have a 2004 Ford Escape. The original tires wore well with the pressure settings recommended on the manufacturer's sticker. However, when I replaced those tires and stayed with the manufacturer's recommendations, the new tires wore at the edges unevenly. So I ran those at the max pressure of 35 psi and they wore much better. Same goes for the tires that replaced those. At 35 psi I got much better tire wear.
On my old '97 Chev truck, I ran D range 16" LT radials. For running around without a load, I got the best wear at 45psi, and loaded at 50 psi. I guess the best rule of thumb is to observe tire wear. If they wear on the edges: increase tire psi. If they wear in the middle: decrease tire psi.
I was a "Buick-man", but always inflated my tires to the max posted on their side wall. Car manufactures want you to have the smoothest ride. Tire manufactures want you to get the longest tread wear.
Happy motoring and HAPPY NEW YEAR!!!!
ps: I run Seabiscuit's tires at 45psi & Sambuca's at 55psi
My 02 Excursion shows 45/55 psi front/rear on the inside door jam. The Firestone Transforce tire itself shows 80 max psi. I've run 70 psi front/rear for the entire life of the truck and get 80 tho miles per set. Sure, it runs a bit rough but it's a truck...what more can be said.....Jerry
I am a bit of a fuel economy nut and always run my tires at 10% LESS than than the maximum listed on the tire. I get VERY good wear, never a problem with the extra pressure and an easy 10 % plus gain in MPG. Yes it does make for a little harder ride.
That old saw about more wear in the center of the tread with higher pressures may hold for bias ply tires but absolutely does not hold for radials (within reason!!!)
Steve, The max pressure for the tire is to run at maximum load at rated speed. We don't do that so less that max is best. Start with the manufactures recommendation. But since tires vary in construction this is just a starting point. With the vehicle on clean pavement or concrete, place a chalk line across a front and rear tire. Roll the vehicle to get a couple revolutions. Observe the chalk line. If evenly worn across the tire, pressure is optimum. If worn in the center too high, if worn on the edges, too low. Adjust pressure a couple PSI at a time until you get the optimum pattern of the chalk line on the tire.
I went to a General Tire seminar for my work. I asked them, the manufacturer, what the psi should be set to? Their reply was the max. pressure on the sidewalk, not what the door jam says. They said this was for best tire wear. So, if the tire says 44psi, I go with 40psi just because it's a round number and easy to remember.