Tech Tip by "allmyEXes" 0319

[allmyEXes]

Some us may or may not think of this at least twice a year but it is past the time to check your tire pressure and adjust for the Winter season. I am in the southeast USA so the climate change here and temperature swings are not as large as other parts of the Country or World. Yesterday when it barely reached 40 degrees F, I checked mine and they were all at 30 psi + or - a 1/2 psi at 800 ft above sea level. I normally run about 35 pounds in mine during the moderate time of the year. Today when it reaches 50 F I am going to add a few pounds up to 34 or maybe 35 since we are about to have a really cold blast coming out of Canada. The + or - a 1/2 of a psi tells me that I probably don't have a minute hole in any of my tires. That's pretty good considering they are 4 years old.

 

[imp]

Some us may or may not think of this at least twice a year but it is past the time to check your tire pressure and adjust for the Winter season. I am in the southeast USA so the climate change here and temperature swings are not as large as other parts of the Country or World. Yesterday when it barely reached 40 degrees F, I checked mine and they were all at 30 psi + or - a 1/2 psi at 800 ft above sea level. I normally run about 35 pounds in mine during the moderate time of the year. Today when it reaches 50 F I am going to add a few pounds up to 34 or maybe 35 since we are about to have a really cold blast coming out of Canada. The + or - a 1/2 of a psi tells me that I probably don't have a minute hole in any of my tires. That's pretty good considering they are 4 years old.

@allmyEXes
What is the maximum tire-listed inflation pressure on the sidewalls? If, like, 44 psi, your 30 psi is rather squishy. If you have 2-ply rated sidewalls and tread both, you could probably not experience tire failure running 26 psi......watch the airwaves explode here! A 70 degree tire at 26 psi climbs to about 31 at 110 degrees, and soft tires get hot quick! Just thinkin'.......imp

 

[allmyEXes]

Thanks imp. I should have mentioned that the maximum tire pressure is embossed on the sidewall. People, check your psi specs to inflate to the proper amount.
Here are the Wrangler Goodyear P23575R15 specs

The 235/75R15 Goodyear Wrangler Radial has a diameter of 28.9", a width of 9.3", mounts on a 15" rim and has 724 revolutions per mile. It weighs 29 lbs, has a max load of 2028 lbs, a maximum air pressure of 35 psi, a tread depth of 13/32" (over 3/8") and should be used on a rim width of 6-8".

Tires rated P when installed on Light Trucks have a 9% reduction in their rating for example .91x2028=1845x4 tires=7380 GVWr. My Explorer weighs approximately 4200# (4166 curb weight according to wikipedia). That leaves 3380# for passengers and cargo excluding trailers. One would tend to think that a trailer that is tongue heavy would affect the GVW too

 

[Mbrooks420]

My TAKOs have a max inflation over 50 and I run them at 35-38.

Tire psi is meant to be checked cold. Where they climb when heated up is somewhat irrelevant. It’s built into the engineering of the tire. People are lazy. Let’s say it’s 80 degrees. You fill your tires to 26 psi. Time passes. You are lazy. More time passes. Winter comes. Cold snap, and it’s 10 degrees. You are now driving around on grossly under inflated tires.

People don’t check their tires enough, if at all. It’s one of the main reasons for oil life monitors and TPMS.

 

[RickOTR]

Tire pressure means nothing when it comes to longevity of a tire. I use the white chalk test when tires are cold to see that my tires are properly inflated and get many miles out of them.

 

[410Fortune]

Great thread!

I agree with @RickOTR
Not one of our vehicles has stock size tires or wheels so the door psi ratings and tire max inflation are merely guidelines

I also use the chalk trick, except I don't need chalk, just drive the truck into the shop our road is ALL MUD right now....it marks the tires perfectly!
If I am going over the road on a long trip I will inflate higher so I get better MPG, this will wear down the center of the tire much faster so if I notice that wear happening (after the trip) then I lower the psi so the sides get even wear. Managing PSI in tires is same as keeping oil at level, considered regular maintenance. I check tire pressure just about every oil change