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What r u guys running psi?

They also seem to vary a lot while running down the road. By "a lot" I mean up to three psi on a tire. Sunshine and pavement temps probably account for some of this.
Tires gain heat when running down the road so the PSI will rise. I see a 5 PSI rise after a freeway run.
On our off road race truck with 40" tires, I've seen up to 15 PSI difference after 150 miles of racing.
 
Being 12 ply doesn’t mean they need less air for the load.

The ply rating (remember they don’t actually have 12 plys) doesn’t effect low load pressures. In your example with 35x12.50-18 a D, E, and F rated tire all can hold the same weight at 50 psi, 2910 lbs. The main difference in all 3 is the max pressure, which limits their max weight.

The D rated tire is limited to 50 psi.

The E and F rated tire can both hold the same weight at 65 psi, 3415lbs.

The E rated tire is limited to 65 psi.

The F rated tire can go to 80 psi and hold 3970 lbs.
All E rated tires i have ever purchased of any brand were 80 psi max so not sure what brand you are referring to that are limited to 65 psi. And when i looked at the weight chart on toyo's site originally before purchasing the f rated tires showed higher weight carrying capacity at 50 psi then e rated 10 ply tires so that's where i got my info from the manufacturer .
 
Being 12 ply doesn’t mean they need less air for the load.

The ply rating (remember they don’t actually have 12 plys) doesn’t effect low load pressures. In your example with 35x12.50-18 a D, E, and F rated tire all can hold the same weight at 50 psi, 2910 lbs. The main difference in all 3 is the max pressure, which limits their max weight.

The D rated tire is limited to 50 psi.

The E and F rated tire can both hold the same weight at 65 psi, 3415lbs.

The E rated tire is limited to 65 psi.

The F rated tire can go to 80 psi and hold 3970 lbs.
The standard max pressures are usually:
P is 44psi max
C is 50psi max
D is 65psi max
E is 80psi max
F is 95psi max
G is 110psi max
 
Hit the scales again Friday. Had the whole family in the cab, 5 people, the dogs and some gear in the bed for a weekend away (that failed, but that’s another story)

5760/4340. Running 57/40 for pressure and it handles great.

Sadly I’d be over GVWR on a 2500. I wasn’t even heavy enough to get into Alt trailer height.

Something has to change on vehicle classifications, this is ridiculous. Luckily GVWR doesn’t mean crap in many states, including Idaho.

The standard max pressures are usually:
P is 44psi max
C is 50psi max
D is 65psi max
E is 80psi max
F is 95psi max
G is 110psi max

For standard sizes yes, but as you can see by the chart I posted not all flotation sizes follow that.

P is also a funny thing, some are 35 and some are 44. XL are 44, but not all load and inflation tables account for that. The toyo table for P tires doesn’t even go to 44 psi, despite them offering tires rated for it.

P are also only rated for 90% of their weight rating on SUV’s and pickups, but nobody ever talks about that.

All E rated tires i have ever purchased of any brand were 80 psi max so not sure what brand you are referring to that are limited to 65 psi. And when i looked at the weight chart on toyo's site originally before purchasing the f rated tires showed higher weight carrying capacity at 50 psi then e rated 10 ply tires so that's where i got my info from the manufacturer .

You should probably look again… there is only one line on the Toyo chart for you size tire and it covers D,E,F rated tires. This chart has been relatively unchanged for 10+ years, so I’m not sure what Toyo chart you looked at.

I have seen a lot of OEM load and inflation tables, and none of them work they way you described for LT tires of the same size with different load ratings.


Lots of floatation tires are 65 psi max for E range tires. The same chart also shows this.

0EE612C6-112A-44C8-98F0-09D13FF7B5E9.jpeg
 
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Hit the scales again Friday. Had the whole family in the cab, 5 people, the dogs and some gear in the bed for a weekend away (that failed, but that’s another story)

5760/4340. Running 57/40 for pressure and it handles great.

Sadly I’d be over GVWR on a 2500. I wasn’t even heavy enough to get into Alt trailer height.

Something has to change on vehicle classifications, this is ridiculous. Luckily GVWR doesn’t mean crap in many states, including Idaho.



For standard sizes yes, but as you can see by the chart I posted not all flotation sizes follow that.

P is also a funny thing, some are 35 and some are 44. XL are 44, but not all load and inflation tables account for that. The toyo table for P tires doesn’t even go to 44 psi, despite them offering tires rated for it.

P are also only rated for 90% of their weight rating on SUV’s and pickups, but nobody ever talks about that.



You should probably look again… there is only one line on the Toyo chart for you size tire and it covers D,E,F rated tires. This chart has been relatively unchanged for 10+ years, so I’m not sure what Toyo chart you looked at.

I have seen a lot of OEM load and inflation tables, and none of them work they way you described for LT tires of the same size with different load ratings.


Lots of floatation tires are 65 psi max for E range tires. The same chart also shows this.

View attachment 55240
I was probably looking at d and f rated instead of e and f but honestly it doesnt matter to me if i was off or not . I was mainly just trying to just give my psi for tire size that i run not get in a argument of who is right on a weight chart .
 
I was probably looking at d and f rated instead of e and f but honestly it doesnt matter to me if i was off or not . I was mainly just trying to just give my psi for tire size that i run not get in a argument of who is right on a weight chart .

It really doesn’t matter what load range you’re looking at, the ply rating doesn’t have any effect on what pressure you run for the weight it only effects the max pressure, which dictates the max load. At 50 psi they both carry the same weight.

Not trying to get into an argument, just pointing how how tire ratings work and how that pertains to the proper pressure for the load.
 
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Hey guys.
Just bought a 3500 and found this thread while searching proper tire pressure. I asked the service manager at the dealer and even showed him a load inflation table. He said stick to 80 like it says on the sticker. Seems ridiculous.
Attached the load inflation table that I've found online for my tire size.
Everyone pretty well agree that it's best to follow the table?
Appreciate any insights.
 

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Hey guys.
Just bought a 3500 and found this thread while searching proper tire pressure. I asked the service manager at the dealer and even showed him a load inflation table. He said stick to 80 like it says on the sticker. Seems ridiculous.
Attached the load inflation table that I've found online for my tire size.
Everyone pretty well agree that it's best to follow the table?
Appreciate any insights.
Yes thats what you follow not the idiot with a clipboard who has no clue what he is talking about.
 
I run 50Psi unloaded all round
60Psi half loaded all round
65/75Psi loaded and van on the back

You’re running 295/70R18’s right?

I think you could run lower pressures, especially in the rear. 50 psi is good for 3,000lbs a tire, and you’re likely lighter than 12K lbs unloaded. 45/35 is all my CCLB 6.7 would need empty.
 
You’re running 295/70R18’s right?

I think you could run lower pressures, especially in the rear. 50 psi is good for 3,000lbs a tire, and you’re likely lighter than 12K lbs unloaded. 45/35 is all my CCLB 6.7 would need empty.
Correct on the tyre size.
Do you have very good even tyre wear at 45/35 Psi ?
 
Correct on the tyre size.
Do you have very good even tyre wear at 45/35 Psi ?

I still have the stock size so I run a little more tire pressure, but with that wider tire on your stock rims you’ll get better wear at lower pressures.
 
All these different pressures. How are y’all keeping the lights off on the dash? I just put new tires on my Hemi CCSB I plan to run 50psi but I cannot stand the dash telling me to inflate tires. How to I reset the Tpms to be happy at my desired pressures. I’m sure this has been answered somewhere but I can’t find it
 
Invest in ALPHA OBD and the Bypass Harness. You can change the Pressure settings and many other things. Check out the Topic for Alpha and also Known Settings.
 
All these different pressures. How are y’all keeping the lights off on the dash? I just put new tires on my Hemi CCSB I plan to run 50psi but I cannot stand the dash telling me to inflate tires. How to I reset the Tpms to be happy at my desired pressures. I’m sure this has been answered somewhere but I can’t find it
I just changed mine. AlfaOBD, bypass cable, and OBD to USB adapter (I used my laptop). That's about $175 to avoid the idiot light, although it will probably prove useful in the future as well.
You'll have to feel your way through installing drivers, getting connected, and saving a backup file. I used this video as a guide for changing the TPMS.
 
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