Truck tire pressure

[JasG]

I run my tires about 10% less than the max listed on the sidewall (ex: 40 psi in my truck tires rated at 44 psi). I don't run the max because if you do then you could easily run well over the max with a change in air temp and/or tire temp from driving. For example, we took a vacation to Florida and drove there (1400 miles). I put the tires up to the max 42 psi figuring we would get better gas mileage. 300 miles later and about 25 degrees warmer, I check the tires at a gas station and they were all at 50 psi. One good pothole and one of those tires could easily blow out a sidewall.

I think the cold pressure takes this into account that the tires will warm up and I don't think 50 or even 60 PSI will cause a failure. Otherwise I would think they would recommend checking pressure "hot". The only time I know this comes into play was with heavy machinery going down the road. Earth moving pans use to be able to be driven down the road and sometime great distances from job to job. I know when my dad did this they would stop every now and then for this reason.

 

[Egon]

Moisture in the aircraft tires can turn into steam under certain conditions. The steam has considerable volume and the tires don't have PSV.

 

[ultrarunner]

Too bad you're not in California where it is the law that anytime a vehicle is in for service, tire inflation must be checked and adjusted if necessary and records kept for 3 years...

Tire Pressure Program

And here is the 5 page law... http://www.arb.ca.gov/regact/2009/tirepres09/tirefinalreg.pdf

 

[deerefan]

All my vehicles, the tire pressure stays between 32 and 38. 32-36 on my wife's Traverse gives it the best ride, 36-38 on my 97 F150 and 11 Z71 give them the best all around ride both towing and regular driving. I had them at 40, but the ride was a little too firm for my liking.

 

[timswi]

I use the manufactuers spec....That's what supposed to be utilized, if you have the recommended tire size, that's what's engineered into the vehicle..

That being said, I run the front's to spec, but run the rears a few punds less to prevent center of the tire wear due to high torque and low rear weight...When I hook the trailer up, I then go to spec. Never had a problem and I get great tire wear.

The sidewall max is only what the tire can take, not what supposed to be done..Besides running a 35lb spec'd tire at 50 lbs will only wear the centers out.

 

[TheTrailerGuy]

No, you're not trying to argue, much less debate. You're merely repeating what you've heard as if it were fact. Since you're TheTrailerGuy I'm assuming a lot of your experience pertains to trailers. All my life I've seen U-Haul rental trailers with big signs on the fenders like "Inflate tires to 60 psi" or something like that. That's if you're hauling the trailer empty or loaded to maximum. The reason is that U-Haul doesn't want to see a tire fail from underinflation. They don't really care if the trailer bounces and rattles when empty or if the tires wear out the centre of the tread from overinflation because they'll probably die of old age before that.

However, this thread is about truck tires. "Trucks" can be a variety of vehicles. If you drive one of those yuppie Porsche Cayenne SUVs, don't want to be inflating your tires to the maximum sidewall number because some redneck in a Ford pickup will be able to outdrive you as you go skittering off into the weeds on a twisty road. Generally, trucks used for personal transportation carrying just the driver should have their tires inflated to the door jamb pressures for best comfort and roadholding. 18-wheelers, however, would probably run the maximum sidewall pressure just to be safe. If they're never carrying a load, they should be in a different line of work.

Ok... i can admit it when i am in error... here is what car talk says about it. I think that i will leave it at that. Car Talk

 

[timswi]

Ok... i can admit it when i am in error... here is what car talk says about it. I think that i will leave it at that. Car Talk

All true....Anyone doing otherwise is playing with fire, or at least their checkbook.

 

[timswi]

One more thing...My wheels were delaminating, so they were replaced under warranty. The dealer put 35lbs on all 4, with a spec of 30, and by the time I noticed it the rear centers were starting to go (apx 1000 miles after the wheel change)..The tire sidewall says max=44lbs..I'd be replacing all four tires by now if I followed the max sidewall advice....I do have "Good For a Year" OEM's though.

 

[Mace Canute]

There's a couple of things in "Car Talk" that are out and out bogus...I wouldn't believe anything that author says. Example...

If tire pressure is too low, then too much of the tire's surface area touches the ground, which increases friction between the road and the tire. As a result, not only will your tires wear prematurely, but they also could overheat.

Under inflated tires overhead because of excessive sidewall flexing, not increased friction from a slightly larger footprint.

A lot of people check the pressure listed on the tires themselves, but that's actually the wrong place to look. The number on the tire is the maximum allowable air pressure not the recommended pressure for that tire when used on your vehicle.

The recommended tire pressure is almost always lower than the maximum tire pressure. Check your owner's manual to find out where to look on your vehicle to find the recommended measurement. This number usually is indicated either on the driver's door pillar, the glove compartment door or sometimes on the gas filler door.

That's the exact reason for all the tire failures years ago on the Ford SUVS. The Fords needed to have a softer ride because of their leaf spring suspension and the way they decided to do it was the cheapest...print a sticker with lower tire inflation pressures to give a softer ride. The same exact tires on other makes of vehicles but with higher pressures had no problems. It also doesn't take into account that the tire on the vehicle isn't necessarily the same spec tire as was installed at the factory, and even if it was, since the Ford SUVs had underinflated specs from the factory, would you blindly inflate your tires to the same pressure that caused all the problems in the first place?

Not that it's related to the tires, but the author makes reference to driving and drinking coffee. (Hint: If you notice that every tie you own has coffee on it, check your tire pressure. It may be too high.) He shouldn't have said anything about it period. It's really called driving without due care and attention and there are many people who have received tickets and been convicted for it. The author is guilty of giving incorrect information and giving information that could give people the idea that doing something is ok when it might get you a ticket.

If you want some information on tires and air pressure, have a read through this very comprehensive site and the links in it also. Tire Tech Information - Air Pressure - Correct, Underinflated and Overinflated

 

[Diamondpilot]

One more thing...My wheels were delaminating, so they were replaced under warranty. The dealer put 35lbs on all 4, with a spec of 30, and by the time I noticed it the rear centers were starting to go (apx 1000 miles after the wheel change)..The tire sidewall says max=44lbs..I'd be replacing all four tires by now if I followed the max sidewall advice....I do have "Good For a Year" OEM's though.

Is this on your new truck? What do you mean by delaminating? The tires or the wheels?

Chris

 

[Diamondpilot]

There's a couple of things in "Car Talk" that are out and out bogus...I wouldn't believe anything that author says. Example... Under inflated tires overhead because of excessive sidewall flexing, not increased friction from a slightly larger footprint. That's the exact reason for all the tire failures years ago on the Ford SUVS. The Fords needed to have a softer ride because of their leaf spring suspension and the way they decided to do it was the cheapest...print a sticker with lower tire inflation pressures to give a softer ride. The same exact tires on other makes of vehicles but with higher pressures had no problems. It also doesn't take into account that the tire on the vehicle isn't necessarily the same spec tire as was installed at the factory, and even if it was, since the Ford SUVs had underinflated specs from the factory, would you blindly inflate your tires to the same pressure that caused all the problems in the first place?

Not that it's related to the tires, but the author makes reference to driving and drinking coffee. (Hint: If you notice that every tie you own has coffee on it, check your tire pressure. It may be too high.) He shouldn't have said anything about it period. It's really called driving without due care and attention and there are many people who have received tickets and been convicted for it. The author is guilty of giving incorrect information and giving information that could give people the idea that doing something is ok when it might get you a ticket.

If you want some information on tires and air pressure, have a read through this very comprehensive site and the links in it also. Tire Tech Information - Air Pressure - Correct, Underinflated and Overinflated

I do not read it that way. I read it that running with under inflated tires causes many problems and he is listing some of the. One being wear and the other heat. He is not saying they necessarily go hand hand hand.

As for the Ford Firestone thing both were at fault. They replaces tons of Firestone SUV and LT tires under warranty on all makes a models, not just Fords. The issue was discovered on Fords because of the failures with the Explorers but my Co-Pilot got his tires on his Yukon replaced for free at the time also. It came from the factory with Firestone's and he simply took it into a tire shop and they put a new set on for free. He has never had a issue and is now on the 3rd set.

Chris

 

[radioman]

You guys are forgetting about the hypermiling techniques.

from thier website Beating the EPA - The Why’s and How to Hypermile - CleanMPG Forums
Tire pressures are a very important key to higher fuel economy. The higher the pressure, the lower the rolling resistance, the higher the fuel economy. The absolute minimum you should use is the driver痴 side door or owners manual recommended tire inflation criteria. This is what the EPA and your car manufacturer sets tire pressures to during the EPA city/highway testing. MAX sidewall is what I would recommend for most as it is well within the safety limits of your car and tire and allows better FE than the pressure listed in the driver痴 side door. I can discuss but cannot personally recommend upwards of 25% higher than MAX sidewall as there are legal constraints we all have to live with. That being said, 50 + #痴 on a MAX Sidewall rated tire leads to even higher FE. Pros, higher FE, less tread wear, more even tread wear across the treads width, shorter braking distances in a variety of conditions, and in many cases, even better handling. Cons, higher NVH (Noise, Vibration, Harshness).

Now that said- I follow the tire max pressures. I ignore the door car specs.

 

[TheTrailerGuy]

You guys are forgetting about the hypermiling techniques.

from thier website Beating the EPA - The Why痴 and How to Hypermile - CleanMPG Forums
Tire pressures are a very important key to higher fuel economy. The higher the pressure, the lower the rolling resistance, the higher the fuel economy. The absolute minimum you should use is the driver逞ｴ side door or owners manual recommended tire inflation criteria. This is what the EPA and your car manufacturer sets tire pressures to during the EPA city/highway testing. MAX sidewall is what I would recommend for most as it is well within the safety limits of your car and tire and allows better FE than the pressure listed in the driver逞ｴ side door. I can discuss but cannot personally recommend upwards of 25% higher than MAX sidewall as there are legal constraints we all have to live with. That being said, 50 + #逞ｴ on a MAX Sidewall rated tire leads to even higher FE. Pros, higher FE, less tread wear, more even tread wear across the treads width, shorter braking distances in a variety of conditions, and in many cases, even better handling. Cons, higher NVH (Noise, Vibration, Harshness).

Now that said- I follow the tire max pressures. I ignore the door car specs.

Radioman.... you are opening a can of worms. Vio Condios my friend... go with God. (I agree but quit speaking about it.)

 

[ultrarunner]

You guys are forgetting about the hypermiling techniques.

from thier website Beating the EPA - The Why痴 and How to Hypermile - CleanMPG Forums
Tire pressures are a very important key to higher fuel economy. The higher the pressure, the lower the rolling resistance, the higher the fuel economy. The absolute minimum you should use is the driver逞ｴ side door or owners manual recommended tire inflation criteria. This is what the EPA and your car manufacturer sets tire pressures to during the EPA city/highway testing. MAX sidewall is what I would recommend for most as it is well within the safety limits of your car and tire and allows better FE than the pressure listed in the driver逞ｴ side door. I can discuss but cannot personally recommend upwards of 25% higher than MAX sidewall as there are legal constraints we all have to live with. That being said, 50 + #逞ｴ on a MAX Sidewall rated tire leads to even higher FE. Pros, higher FE, less tread wear, more even tread wear across the treads width, shorter braking distances in a variety of conditions, and in many cases, even better handling. Cons, higher NVH (Noise, Vibration, Harshness).

Now that said- I follow the tire max pressures. I ignore the door car specs.

Picked up a rental Montana Mini Van once from the SF Airport and as soon as I got on the freeway, I decided to pull off and check tire pressure... pulled into a station and asked the mechanic if the gauge was accurate and he pulled one out of his pocket for me to use... over 100lbs in 3 of the 4 passenger tires!!!

It was a cool day and had only driven about 3 miles.

 

[timswi]

Is this on your new truck? What do you mean by delaminating? The tires or the wheels?

Chris

Just the plastic coating on the chrome..No big deal ..Cosmetic. They replaced all 4 with no arguments and even used stick on weights at my request with no arguments either..Just wish the'd have gotten the tire pressure closer, my fault too for not double checking. Truck was spotless when I picked it up...The GMC dealer here is awsome.

It appears there was a short term bad run from whoever makes the Denali wheels.

I can't believe that people actually run vehicles to max sidewall..The Exploder problems were mostly due to underinflation, and that's the owner's fault. Now we all have these stupid TPMS things that are nothing more than another expensive, useless pieces of garbage...All thanks to the Exploders.

 

[Egon]

I can't believe that people actually run vehicles to max sidewall/QUOTE]

For the last twelve years my truck has been running at maximum sidewall pressure, 80 PSI. Haven't noticed the centre's wearing any faster than the rest of the tires.:thumbsup:

 

[dodge man]

My problem with running higher tire pressures would be the handling. Anything near the max on the tire and it seems like bumps just about kick you off the road.

 

[timswi]

For the last twelve years my truck has been running at maximum sidewall pressure, 80 PSI. Haven't noticed the centre's wearing any faster than the rest of the tires.:thumbsup:[/QUOTE]

You run you pickup tires at 80 PSI, and the centers don't burn out? Not too be smart, but that defies physics unless the truck is only driven on grass.. There can't be more than 1.5 inches of tread contact unless the truck weighs 10 tons...Even then.....

My truck calls for 30PSI by spec, and 6lbs of overinflation caused premature wear on the centers of my rear tires in 1,00 miles..Max sidewall is 44lbs. I would be replacing the tires at 8,000 miles if I did that.

Not arguing...Just sayin'

 

[Egon]

unless the truck weighs 10 tons../QUOTE]

Think that 10 tons is a little heavy for my old truck.

If it's empty I run at 60psi.:thumbsup:

 

[TheTrailerGuy]

That's kind of where I got stuck...but Chris is right, the Michelin site says it plain as day. I would imagine that with a load (like 9660lb) and heat from friction on the road, the pressure probably rises a certain percentage in the tires. I would think that you wouldn't want it rising above the max rating on the tire, so maybe that's why the truck manufacturer sets it at some safe value for all-around use. Beats me but I'll go with that and maybe just up it a little when I'm hauling stuff.

Ok, i happened to be looking for some vintage tires for a buddies old hot rod Cadillac project and while at the Coker tire site, emailed them asking what they recommended as far as following air pressure settings.. meaning, do i inflate to the max PSI on the sidewall, or something else... THEY recommended the following...

Craig,
For a smoother ride and a declined chance of tire issues we suggest running
the suggested air pressure usually marked on the side of your tire from the
manufacturer.

Thank You,
Richard Stephens
Web Support

End of story for me... but i get it won't be the last entry on this thread.