Not a jab at you
@mdh384 or anything but I don't know what you're even trying to say here outside of white knighting.
I do agree with you though, theres a loooot of opinions. Let me try to make sense of some things.
Exceeding load ratings of tires isnt a real concern for anyone here. You can run practically anything if load is the only concern.
Pressures are adjusted for compliance and stability on the part of OEMs and practically mean nothing in upsizing.
That means you can also forget about the 10% adjustment. This is because you can easily meet LT load capacity, but the other inflation aspects can be disregarded and tailored around your use and preferences. No need for dogmatic assumptions.
7,500 lbs (gvwr) into 4 is 1,875 lbs a corner. And tires are all rated for static load, not dynamic forces.
You're going to be just fine no matter what you choose honestly.
Was that your point though? That each tire is a different case? Thats simply not true and this is an area severely misunderstood here.
You proved it yourself, two very different Ps in the same size get the exact same rating.
Tire loads are all practically standardized including the xl rated 50 psi ones and they all are using standardized carcasses, if not the same ones.
They just differ in weight and features with very minute differences in dimensions due to tread, manufacturing etc.
To add to that, load limit scales are not relevent to just pressure, they are relevant to pressure at volume.
And there is a ceiling for all tires, SL (44) or XL (50) or LT etc. Same regardless of size.
This is where that 26 PSI absolute horse-s*** comes from. Adjusting for a metric no one even needs to worry about, load.
P load index 111-117(x) in our case are just based on size and aspect and are standardized across sizes.
XL denotes a higher pressure limit, but i does not change a load profile at all at any equivalent pressure range as shown below for example.
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Its just reinforcement for a higher pressure ceiling for what those increased forces act on the tire.
People are confusing load range and load index. Load index is like for like regardless of the tire or its rating. Contrary to the LT info below actually (well get into that).
Load ranges denote PSI limits as a function of tire construction.
And on top of that, as shown, pressure adjustments past limit in XL are for rigidity and do not increase load. It may be used when towing for example for stability.
Above you are shown two Ps, in different sizes, but exact same load limits while one is SL, the other XL. Both though are 116 ID.
The PSI load limits are identical across the board, and one is no more "strong" than the other in that regard.
Its just that the larger tire has more volume and that same volumetric pressurized air and can hold the same weight despite being a "weaker" SL construction.
Load was never an issue for anyone here. And you literally dont have to look at anything other than the LOAD ID when shopping. IE 111- 118 - 121 etc.
Just meet or exceed that and you are good. And its stamped on every tire made. Even with LTs. It's the same scale being used. And you need not apply voodoo.
The reason why the LTs are a LOWER LOAD LIMIT PER PSI, is because of heat concerns.
On top of that, for the same given volume and pressure, a thicker LT will actually carry more load despite what you see below.
These are not figures of "what the tire can support" these are figures for how much load can safely be run (heat etc taken into account) at that PSI.
LTs are in every metric stronger than Ps, no matter the amount of mental gymnastics people do here.
Do you rationally think, a thicker, stronger, more reinforced tire, in the exact same size, at the exact same PSI can actually hold less weight?
We are skipping common sense to ego boast and espouse BS that actually doesn't even apply to reality.
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It goes back to what me and
@TeCKis300 are harping on constantly, this chart is being severely misused and misunderstood.
Even as far as having bogus claims of 35 PSI minimums that are completely unsubstantiated.
One more thing with the pressures not being equivalent here has to do with rebound. An equal LT at equal pressure with a P will not rebound the same way.
And that means the thicker carcass resists compliance and the compound gives less thus dissipating less force and generating heat whereas the P will give allowing the air to compress inside the tire instead of the tire flexing and heating up.
Running an LT and adjusting for some imaginative ignorant equivalence using a load safety metric is an exercise in futility.
You will literally skid all over the road with some of these Es at 40-42 PSI. It's just dumb, and 50% of people here run them according to these flawed ideas.
This also makes it a pain in the ass to read tire reviews. (horrible in the wet)... Were you at an obscene PSI? Probably so.
Different makes and model tires has literally nothing to do with it...
And more importantly, anyone running 26 PSI please for the love of god, don't do this. It's actually life threateningly dangerous.
Its the only reason i really bother anymore to talk about this subject. Some people just listen to the forum like gospel.
Theres a handful of actual engineers here, and they are also wrong about things often.
I personally don't believe in running ANY upsized P tire on this truck. It just doesn't make sense outside of only Wet/Winter grip considerations.
In order to provide the rigidity and stability you need with that length of a 2 ply toilet paper sidewall, you are running pressures that destroy all the comfort and compliance advantages that tire has to offer. Show me one OEM that does something like an 8" 2 ply sidewall P from factory. You don't see it for a reason. And if you do it aint at no 26 PSI LOAD CAPACITY chart pressure, i can guarantee that. This is all nonsense from the forum
@Tiger Rag .
Would you rather listen to a bogus understanding or someone who has run your exact tire and its exact LT equivalent?
This was said to me from the head of Toyo Engineering and R&D "Any P for P tire swap, MUST BE run at MINIMUM door jamb pressure or higher."
And I'll add to that that any LT swap you do will far exceed the load handling of any P you replaced as long as its bigger, at practically any usable pressure.
Despite what you see above.
But ain't nobody going to listen anyway... Just a bunch of accidents waiting to happen on both extremes of this misunderstanding.
Also chalk test don't really work as accurately well with this weight class of rig that we own.
There is just too much variance in PSI that will still deform the contact patch due to the shear weight on the axle.
Its going to work but it will be a very coarse adjustment window for you.