Tire pressure

[postwick]

The sticker in the door frame of my 2013 SHO says 35psi. The tires I have on the car (with stock wheels) say maximum of 50psi. So where should I keep the tire pressure?

 

[krewat]

Keep them at the point where they don't wear funny and handle the way you want. And that's not a sarcastic answer, it's the truth

Are these the Goodyear F1 tires? If so, I keep mine around 41lbs, front and rear, and rotate them every oil change which for me is at 5000 miles or even less.

I do adjust them, and the tires on my other vehicles, up or down during the rotation interval depending on what I'm seeing for tread wear.

Too much pressure they wear in the middle, too little, they wear on the edge.

 

[postwick]

They're a set of Falken ZE950s. So you do a trial and error method to find your preferred psi? Interesting. I've never heard that, but then again I've never had anything nearing a race capable car before.

 

[krewat]

Others will probably come up with more suggestions, but yes, that's what I do to ALL my vehicles. I watch the tread wear and adjust accordingly.

For certain vehicles I've owned, I also adjust for handling, ride, etc. For the Taurus, I go for handling, but I've been running the Goodyear Supercar F1 tires on my 2013 (returned at end of lease) and the 2016, and so far, when adjusted for treadwear, handle the best overall.

Full contact across the width of the tread makes for more traction, and even tread wear. If that also happens to give you the least "squirm" in the turns, all the better

Some tires I've owned on certain vehicles don't do the best for all three criteria at one single pressure. But for some reason, the Goodyears on my Taurus seem to do exactly that or at least, come close enough.

 

[postwick]

Apparently I shouldn't have relied on the gas station air pump gauge. It said 30psi so I bumped it up to 42. Hard. As. A. Rock.

Checked it with my gauge and it said 48. So I dropped it down to 42. Still a tad hard.

I was mostly just curious what others run since the door says 35 which is quite low compared to the tire maximum of 50.

 

[krewat]

Max pressure on the tire is at max weight rating. You're no where near that unless your car is full of people and the trunk is full of lead

See how it does at 36-38. And watch your tread wear

 

[postwick]

What if the trunk is full of people?

 

[2011TAURUSSEL]

Then you follow the Chicago MOB boss recommendations......

I am in the 34-36 crowd myself.

Whenever I am at Costco I have it topped off to around 40 with Nitrogen then when I come home and they cool overnight I can slowly deflate all to around 35 and start fresh.

 

[SilverSH0]

Max pressure on the tire is at max weight rating. You're no where near that unless your car is full of people and the trunk is full of lead

See how it does at 36-38. And watch your tread wear

Contrary to popular belief, tire pressure doesn't change based on weight. Do an experiment yourself if you don't believe me. Take the pressure of the tire when the car is on the ground, jack the wheel off the ground, and then take the pressure. Both will be the same even though the weight on the wheel changed dramatically.

 

[postwick]

Tire pressure would change based on volume. If the tire is compressed, pressure would increase. But I think in a typical automotive scenario you aren't going to compress it enough to make any appreciable difference.

 

[SilverSH0]

Tire pressure would change based on volume. If the tire is compressed, pressure would increase. But I think in a typical automotive scenario you aren't going to compress it enough to make any appreciable difference.

Yes, if volume changed pressure would change. But volume isn't changing. A tire makes a flat spot on the tread area when on the pavement but the sidewalls also bulge out a little bit. Any volume decrease from the flat spot is made up by a volume increase by the bulging sidewall. No total volume change makes for no pressure change.

 

[ridered74]

I run mine at 35. Tires have almost 30K miles on them and have worn completely even on all 4 tires. Max is the highest it can be before you risk failure. Just like anything, you don't want to constantly be running something at the absolute limit of what it is engineered for, otherwise it will fail long before what it was designed to last.

 

[Auggie]

If your tires are the one's that came with the car you should use the recommend tire pressure that is located on the "B" pillar. If you have changed tire size you can use this trick that I used when I was drag racing. Over inflate your tires then drive on the freeway for 20 min to build up the pressure(3 to 4 #). Find a smooth FLAT road or big parking lot. Use a piece of white chalk and rub it across the tire tread and go for a short ride. If there is still chalk on the outsides of the tire remove some air and do it all over again. Worked for me.

Auggie

 

[Quinnbristow]

One thing you can try is loading the car with whatever weight you generally carry, and draw a thick crayon line from shoulder to shoulder on the tire. Drive around the block, and you will be easily able to see where it's wearing. If it's in the shoulders, (symmetrically from inner to outer) then raise the pressure. If it's in the center, lower the pressure.
If you get outer edge wear, slow down around the corners during your test.

This will tell you the perfect pressure for your car.

 

[postwick]

Slow down in the corners? Blasphemy!