Truck tire pressure

[HiTechTed]

I'm going to ask what should be an obvious question...do I go by the tire pressure rating inside the door panel of my truck, or do I go by the rating on the tire itself? The door rating says 32 front/35 rear, the tires say 44lbs max cold. Since that's a difference of nearly 10lbs I'm kind of curious as to what number should be used, mostly for fuel savings and to prevent premature wear on the tires. I bought the truck used so I'm not sure if the tires are factory or not (they appear fairly new and the truck has less than 20k miles on it).

I try not to ask dumb questions but since this truck is not very kind on the wallet at the gas pump, I want to squeeze as much mpg out of it as I can, but I don't want to over or under inflate the tires.

Thanks.

 

[Diamondpilot]

You should always go buy what is on the door pillar. The tires have a max rating but that is for the tires, they have no idea what vehicle they are going on.

Now I do run my rears on my 1/2 ton Nissan Titan at a few PSI over the door rating of 35PSI. Somewhere around 40PSI but I am towing 9,660# with it each and every weekend about 150 miles.

Chris

 

[tcartwri]

I would totally disagree with that.

Go by the specs on the sidewall of the tire. A light truck tire that is less than 80% inflated is considered a flat tire, and will fail prematurely.

 

[Soundguy]

I use a combo of both. door pillar info UNLESS it exceeds the tire rating.. then always abide by tire max.

soundguy

 

[Diamondpilot]

I would totally disagree with that.

Go by the specs on the sidewall of the tire. A light truck tire that is less than 80% inflated is considered a flat tire, and will fail prematurely.

Not sure where you got your info.:confused2:

Quote from Michelin.
In the vehicle owners manual.
On the vehicle’s door jamb. (Often, a vehicle information placard is located on the door jamb along with the recommended tire inflation pressure.)
Inside the fuel hatch filler flap. (In some vehicles.)
The glove compartment door. (In some vehicles.)

But NOT on the tire. The inflation pressure shown on the tire sidewall is only the maximum tire inflation pressure. In most situations, the vehicle manufacturers recommended tire inflation pressure is shown on the vehicle placard.

http://www.goodyear.com/rv/tirecare/loadinflationtables.html

http://www.michelinman.com/tire-car...re&WT.srch=1&gclid=CJ77qLOZvqkCFUW8Kgod0l94gQ

Chris

 

[Egon]

Wonder if all those folks with the Explorers and exploding Firestone tires followed the door tag for inflation pressure?:

Probably had a very nice ride till they heard the bang.

 

[ultrarunner]

Could have changed... back in the 1960's Cadillacs that we sold from the Dealership listed 16 and 18lbs inflation...

Tire manufacturer's sent out bulletins that using factory specs would provide softest ride at the expense of tire life and high speed handling.

Went to a seminar on tire safety about 20 years ago and said dealer spec is for OEM tire and the best way is to adjust up to 20%, not going over tire max pressure, to get optimum even wear... could also do the wet pad test to see if tire is making full contact...

Also, check inflation before operation.... not after extended high speed use.

All of my info is dated for what it is worth.

 

[paul dyar]

You are telling me to inflate to what is on the door, reguardless of what tire I have on the truck?
Paul

 

[Soundguy]

I'd never inflate past tire sidewall specs

 

[HiTechTed]

You are telling me to inflate to what is on the door, reguardless of what tire I have on the truck?
Paul

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.

 

[FredH]

I always go by what the tire says regardless of vehicle the tire is on . My old '84 Ford F250 has max cold psi of 80 and that is were they are set at . The '06 Dodge 3/4 ton has 65 psi and better half's Saturn SLC has 32 psi .

As mentioned above , The owners of those Ford Explorer's followed the door post and were did it get them ?

Fred H.

 

[Egon]

the Michelin site says it plain as day.[/QUOTE

Yes and nicely absolves Michelin of any responsibility.

 

[sld]

I would never run the max sidewall rated pressure unless I was fully loaded.

As a general rule, I run about 80% of sidewall max for normal driving.

I always ignore the door jamb sticker.

The wet tire track is the very best way to keep your tires wearing flat but it must be done at whatever weight and psi you are running.

 

[arsenix2001]

If your running factory tires or factory spec tires then always go by the door panel, it is the calculated load that the vehicle is supposed to carry based on it fawr and rawr. Aftermarket tires are another story. And the max pressure listed on a tire is just that, the MAX safe pressure to run assuming you are loading it right up to the tires weight rating. Go ahead and do that on a lighter vehicle and have fun bouncing all over the road and wearing out the center of your tires prematurely. And i dunno why all pf the explorer tire comments are being made, that was a defect on firestones behalf that resulted in tread separation.

 

[FredH]

"Defect On Firestone tires that resulted in Tread Separation " ?????????

Never seen that in the news reports . All I ever seen was the " Your Fault , not our Fault" comments From both Ford and Firestone .

Does not matter what brand of tire you run , if you run it under pressurized , You are going to have issue's . Most common issue is heat build-up with subsequent tread separation and blow-out . A REAL common error that many people assume is that all the "gators " , ( Truck tire treads ) that they see on freeways and roads are the results of trucks using retreads . WRONG !!! It is from under inflation , even on Brand new virgin tires .
The higher the psi rating on the tire , the more margin for inflation error you have . Were a Semi tire is 100 psi and 10% less is 90 psi , a car tire at 32 psi has a margin of only 3.2 psi .

My old ford mentioned above is rarely drove except to haul , thus I keep the tires near max cold psi , that and the overload springs make for a stiff ride anyway when empty . "Wear" is a experimental research project to find the best psi for a given vehicle , tire and placement combination .
Example : My ex-truck had a 234" wheelbase and the steer tires lasted the longest with the best wear at 110 psi while the truck I have now has a 265" wheelbase and It likes 105 psi . That is a 5% swing ( 4.6 or there abouts actually ) , But on semi tire's that is within a inflation margin that is acceptable without damage to tire .


Not a Tire expert , Just someone that drives more miles in a month than most do in a year .

Fred H.

P.S. I am in no way bashing Ford or Firestone , I myself would lay most of the blame on the owners of those vehicles in that whole mess for lack of common sense . Tragedy , Yes , Lives were lost but over the years , people have lost a lot of what would of been normal common sense in past society . Example , Flat tires . How many times do you see people blazing down the freeway at 65 mph + on one of those temp spare tires ??? ( that have a max rated speed of 45 mph. ) . I see it every day . Is that the tire maker or the vehicle maker's fault when that tire goes and the car crashes ??? Just food for thought .

 

[powerstroke444e]

It just depends on what you do with your truck. My trucks I run the tires at the max PSI on the side wall which is usually 80psi on most 16 tires. As I want to be able to haul max load without airing up the tires.
On my car I find the psi on the door is to low as tires feel soft and dont take corners as well so I am found 37 psi does the best on it vs the 32 on the door and I get about 50K out of the tires this way or about a 1-2yrs I drive alot in my car and I have same type of car for last 10yrs I be a creature of habit I guess.

 

[dodge man]

I live out in the country, and if I ran anything near the max listed on the sidewalls, it would bounce me off the road. Unless I'm hauling a heavy load, I run what is on the door jamp sticker, or just a little bit higher.

 

[Mickey_Fx]

As an owner of an RV, here's my take.

Weigh the rig, front and back axle separately. Refer to an inflation chart for the size and load rating for the tires then look for the nearest load your tire is carrying, for that load a pressure will be given. Now that is the min/proper pressure for that load. Unlike car tires, LT tires give max load at min pressure.

On my MH, there are 2 separate inflation stickers found on the door jam and they don't agree. One is from the chassis maker, the other from the coach maker. Only one is correct. For my tires the max rated load can be carried @~ 5psi under the load/pressure info found on the tire sidewall. I typ carry an additional 2psi to account for small weight changes.

Look at the pic and you will see max load stated, not max pressure.

 

[JasG]

If your running factory tires or factory spec tires then always go by the door panel, it is the calculated load that the vehicle is supposed to carry based on it fawr and rawr. Aftermarket tires are another story. And the max pressure listed on a tire is just that, the MAX safe pressure to run assuming you are loading it right up to the tires weight rating. Go ahead and do that on a lighter vehicle and have fun bouncing all over the road and wearing out the center of your tires prematurely. And i dunno why all pf the explorer tire comments are being made, that was a defect on firestones behalf that resulted in tread separation.

The reason for the firestone comments was it was a Ford issue. The tires were fine until Ford lowered the door panel from 34 PSI to 28. The same tire on F-series trucks was listed at 34, that too me is a huge difference. One way to tell if your tires are properly inflated is to check the temp after a while of driving. Under inflated tires heat up a lot more and fail. Those tires at 28 psi on an explorer were overloaded.

Our last company F-350 had 4 ply tires from the factory and listed 36 PSI, yet the front axles were rated way over that. The dealer had to replace the tires with 10 ply at 80 PSI due to the truck was overloading the tires when we put the snowplow on. The truck had the plow prep package from the factory, yet came with tires not rated to carry any more than the front end of the truck. So much for it being calculated from the factory.

 

[arsenix2001]

The reason for the firestone comments was it was a Ford issue. The tires were fine until Ford lowered the door panel from 34 PSI to 28. The same tire on F-series trucks was listed at 34, that too me is a huge difference. One way to tell if your tires are properly inflated is to check the temp after a while of driving. Under inflated tires heat up a lot more and fail. Those tires at 28 psi on an explorer were overloaded.

Our last company F-350 had 4 ply tires from the factory and listed 36 PSI, yet the front axles were rated way over that. The dealer had to replace the tires with 10 ply at 80 PSI due to the truck was overloading the tires when we put the snowplow on. The truck had the plow prep package from the factory, yet came with tires not rated to carry any more than the front end of the truck. So much for it being calculated from the factory.

I hear what you are saying about ford lowering the door pressure, and im sure that was a big contributing factor but it isnt the whole story... Firestones tires were especially prone to tread separation which was possibly due to the run being made during a labor strike at the plant. Faulty tires played a roll as well which is why a bagillion were recalled and exchanged. If it were all an air pressure issue then why didnt they release a tsb with an air pressure change. Fact is it was a muddy situation noone wanted resposibilty for, but to use that as an example to tell people not to follow door recommendations is rediculous. Use common sense when loading your vehicle heavy, calculate the load and add air over the spec if nessesary.