Tire pressure for even wear and comfort

So hear me out...
Ive always set tire pressure to window sticker but at $300 a tire im covering my basis...
Were talking a standard load tire, my falken wildpeak at4's 285 70 17 standard load rating, or any standard load a/t tire....
When discount tire installed the tires & wheels, I ran it by them, are you sure you set tire pressure to 32psi?
As lat time you had tires over-inflated quite abit..
Tech responded we suggest you run these tires at 35psi instead of 32psi, it really promotes even wear & helps prevent the edges of the tire from wear...
Also cooler weather right now, they will drop..
ok...
Next day called the store to cancel the black lugnuts & manager answered the phone.
I run the scenario by him & he pretty much repeated what the tech told me...
Im scratching by head as in my mind over-flating causes center to wear faster, along with stiffer ride...
I had to talk to Wescott Designs as they wanted pics of the truck, ran it by Jason as it wasnt sitting well with me.
Jason responded with we set our tires at 38psi, cuz Jeff said to, we run them higher than the door sticker also but he really didnt know why...

I contact Falcon, They wanted to know stock tire size & door sticker psi #32...

Their response:
"oem tire size & sl rating has a load capacity of 2354 lbs @32 psi per tire.
This is the load capacity you want to meet or exceed on a non lt tire.

The new tire size 285 70 17 has a load capacity of 2368lbs @ 30psi
This is the recommended tore pressure for everyday use 30psi


30psi supports the vehicle load capacity & optimum tire air pressure for even tire wear & ride comfort.

You can run higher tire pressure at your own discretion but over inflation over time in center tread wear which voids your warranty"

WTF???
Who's right!!!

Ide prefer the lower pressure due to would imagine it would improve the ride comfort.
Even tire wear is #1...

 

Falken would be right in this case. The way they did it by calculating factory tire load capacity based on stock pressure and size and then figuring out where the new size needs to be to match that capacity is absolutely the way it should be done. Unfortunately, tire salesmen/installers generally don’t know shit about how tire pressure works and so they don’t do any of that.

If I owned a tire shop, I’d drill it into the guys heads how to calculate the proper pressure and I’d send cars out the door that way. Not some arbitrary number that I randomly thought sounded good, which is what 99% of tire places do.

 

Chalk test…
https://m.youtube.com/watch?v=e7zV2XrSIYU

 

That being said, air pressure stickers are all the same on various trim levels....
Would imagine a sport weighs minimally more than an sr5...
sr5 comes with 245 70 17's
Appreciate the knowledge...

If I put thes falken WP 285 70 17's on the sr5, would falcon have said 30psi also?
just trying to make sense of this!

 

Tire pressure stickers are not the same on all trims. They do all equate to about the same capacity but most of the trucks are not that big of a difference in weight. They basically recommend a different pressure for each different size/load to achieve roughly the same capacity on all the trims. Each truck should get a different sticker depending on trim.

Meanwhile airing the 285/70s up to 35 or 38 psi would have more load capacity than a stock tire on an F-150, which is definitely not right.

if you had an SR5, they’d use the stock pressure and tire size on it and would have calculated accordingly. It would probably end up with the same 30 psi recommendation, but depending on rounding, maybe +- 1-2 psi.

The technical calculation for an SR5 using 245/70R17 110T @ 35 stock psi = 29 psi on 285/70R17 116T. So in that case if you had an SR5, Falken should have in that scenario recommended 29.

 

I know my 24 sr5 & sport both had 32psi on the door sticker...

 

Well they shouldn’t, according to the owner’s manual. Any chance the SR5 was 245/75 and not 245/70? Everything in the owner’s manual says 35 psi for 245/70 and the door sticker should reflect that.

 

I'd do a chalk test to get a ball park estimate for your exact truck

 

Pretty sure it was 32 maybe mistaken but don’t think so..
no longer have the truck but if I remember correctly, 32 psi on the door sticker, 245 70 17
Sure, there’s plenty of guys on here that have us are fives that can verify

 

Chalk test on 285s usually results in super low pressure.

I'd run 30 cold months and 35 summer months and dont worry about it.

Biggest thing with all terrains is diagonal tire rotations help the most with edge wear. All AT tires have edge wear issues regardless of pressure, but you can fight it by reversing the tire rotation.

 

We as a whole at the dealership at Ford always moved the The rear tires directly to
The front and when we moved the front tires to the rear, we would always cross. Didn’t matter if it was front wheel drive or rear wheel drive, and our mind it was the consistency that counted.

 

So we have an old Lexus es300(basically a toyota camry sedan) and the tacoma and both spec low 30s tire pressure and I think it is for similar reasons. Tire pressure effects various things such as tire wear, ride quality and fuel efficiency but in both cases I think the priority is working with the way they tuned the suspension in order to attain a desired ride quality. Other similar vehicles to the es300 with similar stock tires are speced at much higher pressures.

I have come to the conclusion that basically anything between 30 and 45 on a modern tire and resonable loads is probably going to show minimal differences in tire wear. At the higher end you will probably get very slightly better fuel efficiency and on road handling while at the lower end you will get a softer ride. If you want to optimize for tire wear do a chalk test but you can also just watch the wear over time with whatever end of the spectrum you decide on and adjust if you notice excessive wear.

 

In my experience, most of what you said rings true, except for the handling. I’ve found that being overinflated, even if only by 5 lbs or so, drastically affects handling in a negative way. Quick maneuvers at speed in my experience respond pretty terribly if the tire has too much air.

 

If it is really too much then I could see the center bulging and negatively effecting traction. Stiffness can benefit handling in a lot of ways mainly by decreasing roll but if it doesn't work right with the suspension and you lose ground contact from it then you will have bad effects. But in a reasonable range I would generally expect lower pressure being smoother/bouncier and higher pressure being better fuel efficiency and firmer, more grounded and controlled.

 

Ride comfort isn’t terrible at 35 but I can definitely tell it’s more rigid and I feel minor cracks while driving down the road but tolerable and these are just standard load rating tires…
More than likely tire pressure decrease would improve that drastically, just shocked that falcon said running the tire at 30 PSI would be optimal…
Obviously, from the responses here, falcon is on point, guess I learned me something…

 

Weigh the vehicle on scales as you normally drive it

Then do the math Falcon provided, which is correct.

This eliminates confusion over the factory sticker recommendation.

10* temp change = 1# fluctuation, up or down.

 

Chalk test man

 

when i first got by truck from dealer at 7 miles im driving home and im like man this thing rides worst than my 100k mile 2016. i get home and check tires. 50psi. lower them to 35. ok this is better but still feels more firm/rigid then old truck. down to 31 rides better. mine is hybrid , i here alot of people saying new truck rides better then old gen ive never driven a none hybrid i wonder if they use different spring weights?
my truck is also bog stock empty bed.
anyway i think the new gen needs to have tire pressures right at door spec to rid "good"

 

My sr5 is 35

 

Got it, I stand corrected, it’s been a minute…

also seen on a recent thread on another forum, where a bunch of people also complained that their factory tires were way over inflated, on this sport I experience the same thing, ride was really jarring and when I got it home, I checked tire pressure and they were all set at 45 psi on the factory tires. Common and I guess PDI guys are obviously not verifying tire pressure.