What is your tire normal pressure?

[Ultra-HOG]

A lot of members have reported that their dealer did not set the correct pressure prior to delivery. I recall someone saying that theirs was incredibly high, in the mid 50s if I recall correctly, for some reason. Others were very low. Mine do loose pressure slowly, which is normal. If I don't check it for a month all four will need to have air added.

[Dragonslayer]

I admit to not checking the tire pressure regularly and let the dealership shop do it when I have the oil changed. I saw last week that it was at 28 psi and am going to raise them to 34 for a hoped for improvement in mpg's. I get almost 21 when I make a long road trip, which is rare, and 13.5 to 15.5 city mpg city, which is 90% of my driving or more.

[Lex Luthor]

I just purchased my Ridgeline and I am at 32 lbs. I am considering switching to NITROGEN. I would appreciate any feedback on this. There is a great deal of publicity that it is more stable and maintains a more constant pressure over the longer duration. There are claims that NITROGEN filled tires run cooler and will extend mileage. Any ROC members switched to NITROGEN yet?

Lex

jimmybecnel@cox.net

[Pug]

Although I've not tried the nitrogen in my RL's tires, friends have told me that their switch to nitro seemed to offer them "less swing" in their vehicle's tire pressures.
By "less swing", I'm referring to the difference between when the tires are in a cool ambient temperature, at rest, and a hot ambient temp being driven.

Funny that this thread would be resurrected now, being I just checked my tires a couple days ago. I run them at 34psi (cool, in the morning, in the driveway), but when I checked them at the gas station where I fill them, they were all at 39-40psi! I was tempted to release some of the air, but decided not to do so, as the ambient air temp was in the 90's.

I just went out and checked the tires (80deg ambient air temp), and the driver's side tires in the shade are at 34psi. The tires on the passenger side in the sun read 36psi. I suppose it wouldn't take long to bring the driver's side tires up to the pressure of the other side, once I drive for a few miles.

My reason for running the tires a couple psi higher than recommended stems from the TPMS indicator alarming when it got very cold in the wintertime. The extra added 2psi gave a "better cushion" for when the pressure dropped in the very cold ambient air. No more "false alarms".

But now, during the summer months, I'm concerned that while I'm actually driving the truck, with the elevated ambient temp's, the tire pressures may be higher than the "max" recommended for the OEM Mich's.

Should I go ahead and reduce the pressures for the summer?
WWRD? (What Would ROC'rs Do? )

[ChrisM]

My Nissan Quest has the active TPMS system on it where you can see your tire pressure on each corner as you drive. I run mine at about 34 cold but the very quicky go up to around 40 while driving so I think it's normal.

[MRobinson76]

at 75 deg ambient air temp mine all read 33.5 and that is how they came from the dealer (less than a week ago)

[xridgelinex]

I like to keep it around 34psi year round. For the summer I back the pressure down to 32.5psi @ 70. This allows me to keep the pressure around 34 for the changes for temps normally in the high 80's, and especially for those sweltering days on the blacktop.

For those that don’t know, 10 degrees fluctuation changes the psi by ~1psi…

[Pug]

Originally Posted by xridgelinex

For those that don’t know, 10 degrees fluctuation changes the psi by ~1psi…

That's what I thought... at least it's what I've been told... haven't really looked into it on my own.
I wonder what would explain the 5psi pressure shift I experience. Does the air in the tires REALLY get THAT HOT. At 70deg's and 34psi, that would mean that a 5psi rise in pressure (39psi) would have my tire's air at ~120deg's.

If nitrogen shows less of a fluctuation, I may have to rethink having it "installed".
Cooler rubber seems like it would have a longer lifetime, but is 120deg's+ tire-air temperature something that is considered "normal", or has it been found to be just another thing, in this day and age, that can be dealt with?

[xridgelinex]

Originally Posted by Pug

That's what I thought... at least it's what I've been told... haven't really looked into it on my own.
I wonder what would explain the 5psi pressure shift I experience. Does the air in the tires REALLY get THAT HOT. At 70deg's and 34psi, that would mean that a 5psi rise in pressure (39psi) would have my tire's air at ~120deg's.

If nitrogen shows less of a fluctuation, I may have to rethink having it "installed".
Cooler rubber seems like it would have a longer lifetime, but is 120deg's+ tire-air temperature something that is considered "normal", or has it been found to be just another thing, in this day and age, that can be dealt with?

There is more then just "ambient" temperature that plays a role in tire pressure fluctuations... What your RL is parked on and how much sunlight on the tires will make a difference. Ever take the temperature of the blacktop in direct sunlight? Here is a test for you... park your RL so that one side is in direct sunlight. I guarantee you will see a difference in 1-2psi from the one side of the vehicle to the other... and the kicker is that the ambient temperature has not changed.... So to answer your question, YES, the temperature of the tire itself or what your tires are sitting on may be well over 120 degrees.

[xridgelinex]

Originally Posted by Pug

If nitrogen shows less of a fluctuation, I may have to rethink having it "installed".

Nitrogen will show less pressure fluctuations because you take out the water component, (even though very small in percentage in “atmospheric” tire air), condensing and vaporizing during the temperature changes.