[my2cents]

Hi all,

...."Air pressure increases or decreases by 1psi to 2psi for every 10° temperature change." I can't post a link to the site, but it's "tiregrades dot com slash tire-maintenance slash pressure slash what-temperature-is-cold-tire-pressure."

But my question is, what does the manufacturer consider the actual ambient temperature cold tire pressure is when calculating the recommended cold tire pressure?

Thanks!

Cold refers to the tire pressure taken first thing in the morning (before driving the vehicle) after sitting all night.
Tire pressures change with air temperature. The 1 psi for every 10 degrees temperature change is a generally accepted estimate.
The recommended cold tire pressure is the same regardless of the ambient air temperature.
To say it another way... I live in Michigan and my morning temp is 45 degrees...I set my tire pressure at 35 psi...you live in Florida your morning temp is 65 degrees...and you set your tire pressure at 35 psi. You drive to Michigan today and check your tire pressures tomorrow morning at 45 degrees...and it's 33 psi...I check my tire pressures and it's 35 psi. If you want to maintain a 35 psi spec you can borrow my air compressor.
The ambient air temperature is what it is wherever you are. But 35 psi is always 35 psi

 

[Wrecker]

I always inflate my tires to 41 PSI. Generally, I take the maximum PSI stamped on the tire minus the recommended manufacturer suggested PSI and divide in half.
The Goodyear Assurance tires have a maximum load weight at 50 PSI and the recommend PSI is 33. 50-33=17. 17÷2=8.5. 33+8.5=41.5.
So, to me 41 is perfect.

 

[stalag]

I drove a Lincoln Town Car Cartier L with P235/70R16 tires on the vehicle. Ford recommended tire pressure was 32 PSI for the tires. At 32 PSI I got a very cushy ride, but the car steering was like trying to ride a wounded hippo due to the flex in the sidewall. This vehicle has a curb weight of 4400 pounds which is far heavier than the 2021 Escape I now drive. Given this, the maximum cold pressure ( without driving ) located on the tires I had were 51 PSI for the Hankook tires and 45 PSI for the Firestone Winterforce tires. I ran the car on the Hankook tires at 45 PSI and the Firestone winter tires at 40 PSI. The handling characteristics were greatly improved and as such I never saw overinflated tire wear at those pressures on my vehicle. A prior poster here gave a calculation that as a scientist makes sense to me. But it is critical you do NOT exceed the maximum pressure value on the tire itself. Above the max tire pressure embossed on the sidewall will guarantee overinflation. Tire manufacturers design max load at the max PSI located on the tire sidewall. Car manufacturers determine pressure by considering handling and load characteristics expected for the vehicle running that particular tire size. In general the first number on a tire is the width of the tire tread in contact with the road in millimeters. The second number on a tire is the percentage designating the height of the sidewall. The higher the percentage of that second number the softer the tire will handle. The R18 tire on my Escape from Ford is a 55 profile tire vs. the R16 at 70% for the Town Car. Given this, each situation is a bit different but the 36 PSI for my 2021 is a far better choice and the lower profile tire means that the current tires I am using for my Escape have drastically different characteristic for the tires on my Town Car given the latter vehicle weighs 1000 pounds more and had a much higher profile tire. You can run a higher pressure for your Escape but don't exceed the sidewall tire pressure and watch tire wear. You can overinflate a tire that is not carrying a load commensurate with the needed tire pressure. It would behove the OP to look up different tire wear issues that indicate problems with suspension damage/suspension alignment/inflation issues. If maintained properly your tires should wear evenly and your vehicle drive safely. I will point out that damage to suspension, brakes, or tires in any combination can lead to catastrophic failure at speed. It is noted by this scientist that the stops resulting from failure of brakes/suspension/tires can lead to out of control and potentially lethal results to the operator of said vehicle at speed. Educate yourself.

 

[stalag]

I drove a Lincoln Town Car Cartier L with P235/70R16 tires on the vehicle. Ford recommended tire pressure was 32 PSI for the tires. At 32 PSI I got a very cushy ride, but the car steering was like trying to ride a wounded hippo due to the flex in the sidewall. This vehicle has a curb weight of 4400 pounds which is far heavier than the 2021 Escape I now drive. Given this, the maximum cold pressure ( without driving ) located on the tires I had were 51 PSI for the Hankook tires and 45 PSI for the Firestone Winterforce tires. I ran the car on the Hankook tires at 45 PSI and the Firestone winter tires at 40 PSI. The handling characteristics were greatly improved and as such I never saw overinflated tire wear at those pressures on my vehicle. A prior poster here gave a calculation that as a scientist makes sense to me. But it is critical you do NOT exceed the maximum pressure value on the tire itself. Above the max tire pressure embossed on the sidewall will guarantee overinflation. Tire manufacturers design max load at the max PSI located on the tire sidewall. Car manufacturers determine pressure by considering handling and load characteristics expected for the vehicle running that particular tire size. In general the first number on a tire is the width of the tire tread in contact with the road in millimeters. The second number on a tire is the percentage designating the height of the sidewall. The higher the percentage of that second number the softer the tire will handle. The R18 tire on my Escape from Ford is a 55 profile tire vs. the R16 at 70% for the Town Car. Given this, each situation is a bit different but the 36 PSI for my 2021 is a far better choice and the lower profile tire means that the current tires I am using for my Escape have drastically different characteristic for the tires on my Town Car given the latter vehicle weighs 1000 pounds more and had a much higher profile tire. You can run a higher pressure for your Escape but don't exceed the sidewall tire pressure and watch tire wear. You can overinflate a tire that is not carrying a load commensurate with the needed tire pressure. It would behove the OP to look up different tire wear issues that indicate problems with suspension damage/suspension alignment/inflation issues. If maintained properly your tires should wear evenly and your vehicle drive safely. I will point out that damage to suspension, brakes, or tires in any combination can lead to catastrophic failure at speed. It is noted by this scientist that the stops resulting from failure of brakes/suspension/tires can lead to out of control and potentially lethal results to the operator of said vehicle at speed. Educate yourself.

I found this on a cursory search

Wheel Alignment And Tire Wear Patterns | Mike Duman

If driving down a highway requires your steering wheel to be turned at a crazy angle, it may be time for an alignment check. Proper alignment makes driving safer, more comfortable, and less expensive. In this article we will discuss alignments and how

mikeduman.com

Based on my knowledge on the topic this is a good starting point for understanding tire wear.

 

[stalag]

Oh, there are charts for vehicle weight vs. tire pressure put out by a tire manufacturer to help calculate a proper inflation given a particular load. Loading 1000 pounds of gear and people is very different than a 200 pound person. Most vehicle OEM tire inflation pressures are meant to help maximize safety and fuel economy today. This was NOT necessarily the condition back in the day. The Ford Explorer that came equipped with the Firestone 721 radials in the 1970's and 1980's were running so low of a tire pressure that the tires failed as much by heat due to rubber squirming too much as much as a catalyst used in the tires that caused delamination of the tires in question. There were massive lawsuits between Ford and Firestone over this back in the day. The federal government also got involved with this as it was a serious safety issue. Ford OEM pressure was 26 PSI and Firestone for the same vehicle recommended 32 PSI. In this case Firestone was actually right and Ford engineers muffed that one. No vehicle manufacturer wants to repeat this and as such tire pressures suggested by vehicle sticker are a good choice for today's TPMS equipped vehicles.

 

[capmac82]

Tire Pressure gets complicated. The tire makers do so somewhat independently of car makers (if somewhat dependently of wheel makers).

The auto makers often survey persons driving test tracks for their impression of '"best ride" to inform the TP put on the door pillar.

We, as drivers, of course, want different things at different times.

In my 2008 Gen2 Escape, I would go with 38 all around before highway travel. This would get me about 4mpg 'extra' over just highway driving. But, it was not fun for surface roads and potholes, or just less-even pavement. With my 2011, I was using 34/36 which seemed to suit the i4 and AWD on that ride. But, most of the time 34 was my aim point.

So far, from the recommendations above, my 2022 seems to have the right compromise using 35 all around, as measured first thing in the morning. This being Texas, that's not always the factory spec of 60°F--at least not until recently with the weather change.