I understand that one all to well... *L*

 

leaving 1 psi to the max is cutting it a little close IMO. tire pressure can increase up to about 4 psi from cold to warm. In this case, your tire is 43psi cold, maxes out at 44psi and can hit 47psi while you are driving. I agree with pressures above the door label, but I do not exceed 4 psi below the tire max for this reason. That being said, you have to use logic to determine what is good for you. My Scion recommends 29 psi on all tires and the max is 44 psi. I have them inflated to 35 psi for all-purpose and winter driving. In the summer, I plan to run the new ones at 38-40 psi, depending on how they feel from driving a few hundred miles at different settings.

 

Is the manufacturers psi rating based on ride quality or fuel economy? Regardless of what it's based on that can't be a valid number for most vehicles with aftermarket or oversized tires...

 

nah ..... aftermarket rims that are larger than OEM and have smaller sidewall tires need to be inflated more.

 

I usually run 38psi in the fronts and 36psi in the rears (hot). The tires will be cooler and less rolling resistance and I think the car handles better, but you will have a harsher ride. Keep in mind that whatever you set them to, you want the tires to wear evenly. Running over some mud and seeing how the wear pattern goes is always a good thing. The muscle car guys used to spray some paint across the rear treads and drive the car a few miles to see how the tires are wearing. Also, are you checking your tires when they are hot or cold?

 

Warm/hot pressure is unreliable and incosistant. Always check pressure cold.

If you take a bunch of right turns on the way to the gas station, the left tires will be warmer. Maybe not enough to make a differance, maybe so. Better off having a solid number to base your pressures on. ...... unless you have computerized datalogging capabilities tied to a TPM system, but only race teams have that ..... and very few of them even.

 

The rule of thumb is check them cold. IMHO, tires are driven more when they are warm than cold. If you set them when cold, each tire will expand the air differently when warm, hence when checked cold some tires will not heat proportionaitly to all four tires when warm. So if you wanted two lbs less in the rear and you set it to that at cold, when the tires are warm, them final driving temp will be different. About 1lb increase for every 10 degrees. Best to check both.

I guess is the max tire pressure for hot or cold setting?

Again, this is just MHO.

 

I'm not sure, but I think that the max pressure rating of the tire is an absolute number, meaning that it applies to hot or cold. ..... MAX psi.

I understand your point about drive tires warming more than non-drive tires. I also agree with taking note of hot pressures, but the cold numbers should be use for setting the pressures for consistancy as noted earlier.

 

I like to paint and mud idea. Actually, running my tires the way I have (at the 1-2 psi below max) over the last 10 years or so with proper rotation and balancing has gone really quite well. The tires are lasting as they should with no wear or suspension problems. (knock on wood)

 

Pressure on the tire is max cold only. Isn't applicable to a warm tire.