What PSI do you run on your tires?

[Putters]

Originally Posted by KDulcimer

I'll be honest, I don't see any point in raising tire pressure. Any pressure above what the car manufacturer tells you, and you're simply eating up your tires. You'll save a penny on gas and spend 10 cents on tires.

Run it at stock pressure.

If you want to save a buck on gas, buy it in bulk whenever it's cheap. That has a LOT more to do with your cost per mile for gas than your tire pressure.

Reminds me of an episode from "it's always sunny in Philadelphia" the gang solves the gas crisis, one the more memorable shows in the series.

[IsaacCarlson]

What's a guy doing on here telling people to run low tire pressure? Lol.

In all seriousness, anything under 35 is low/flat.

[RedDevil]

"Do not modify your car for economy"

[Fat Charlie]

Cargo capacity aside, the biggest difference between passenger vehicles and big rigs is focus. Work trucks are meant to haul as much stuff as possible as cheaply and reliably as possible, while passenger vehicles are about "image" and a cushy ride.

If I had a long-haul freight truck, I wouldn't second guess the engineers on efficiency. But your average, run of the mill car is a sloppy POS designed to be cute or manly or whatever. Mod the hell out of it.

[Taylor95]

Originally Posted by Fat Charlie

Cargo capacity aside, the biggest difference between passenger vehicles and big rigs is focus. Work trucks are meant to haul as much stuff as possible as cheaply and reliably as possible, while passenger vehicles are about "image" and a cushy ride.

If I had a long-haul freight truck, I wouldn't second guess the engineers on efficiency. But your average, run of the mill car is a sloppy POS designed to be cute or manly or whatever. Mod the hell out of it.

It is impossible to know just how much engineers sacrifice on cars to limit NVH...

It is interesting to note that out of 60 votes, nobody here inflates their tires under 35 PSI. I'll admit that I used to keep mine at 32 PSI. I have them at 38 now, and it seems better. I would like to experiment with higher pressures when I get new tires since mine are so worn down.

[Piotrsko]

Originally Posted by Taylor95

It is impossible to know just how much engineers sacrifice on cars to limit NVH...

It is interesting to note that out of 60 votes, nobody here inflates their tires under 35 PSI. I'll admit that I used to keep mine at 32 PSI. I have them at 38 now, and it seems better. I would like to experiment with higher pressures when I get new tires since mine are so worn down.

That's because I don't own a jeep or pinto anymore with grossly oversize tires which both ran at 10-15 psi

I cant drive the f250 @ 32, it's flat for all intents and purposes.

[slowmover]

Originally Posted by Piotrsko

70 front 55 rear unloaded in F250, 40 front 36 rear Golf, 45 all 4 in Ranger.

All based on actual 100% tread contact with road.

An unreliable method. The single one accurate is to pressurize to heaviest tire load per axle. See CapriRacer posts and website.

[Piotrsko]

Originally Posted by slowmover

An unreliable method. The single one accurate is to pressurize to heaviest tire load per axle. See CapriRacer posts and website.

Why is it unreliable other than the limits of the thermal scan accuracy? I axle weighed the F250, this was the result unloaded. When it's loaded the pressures increase on the rear, but not much on the front, the result of weighing the axles loaded.

[Plasmajab]

Weirdly enough.. My trucks door panel says 35 psi. But I noticed on my last ones that the outer edges on all four tires are worn.. I religiously kept them at 35, but now Im at 40 to see if it makes a difference in tire wear. Regardless of the fuel economy.

[CapriRacer]

Originally Posted by Piotrsko

Why is it unreliable other than the limits of the thermal scan accuracy? I axle weighed the F250, this was the result unloaded. When it's loaded the pressures increase on the rear, but not much on the front, the result of weighing the axles loaded.

It's unreliable because it assumes that even loading/even pressure distribution/even wear is what the tire was designed to do. As a tire engineer, I've designed tires to purposely wear unevenly when loaded per the load charts in order to improve rolling resistance.

Second, it is also possible to design a tire that has good contact for a large range of loadings/inflation pressures. In that case, it would be hard to determine what the optimum inflation pressure would be. I certainly would expect a layman to be satisfied long before he actually gets the optimum value.