Determining Oversized Tire Pressure

[JED]

In an earlier post that received no replies I asked what PSI people were running in 285/75R17 load rated C tires.

Searching the internet found vehicles with similar GVWR’s of 6300 lbs. varied greatly from 28-40 psi for highway travel.

Internet review of chalk testing recommended procedures were all done on cold tires. I would think it would make more sense to determine hot temperature psi’s and adjust from there?

Tire Rack had no input. I’m currently experimenting at 37 front and 35 rear. Any thoughts on that would be appreciated.

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[RFish]

I'm running in that 33-35 psi range

 

[mcrwlrpro]

Minimum 35, so you should be good.

https://tiresize.com/pressure-calculator/

 

[JED]

I'm running in that 33-35 psi range

I think that’s about where I’ll end up

Minimum 35, so you should be good.

 

[Miqie]

Minimum 35, so you should be good.

Do you have a link for this pressure calculation page?

 

[mcrwlrpro]

Do you have a link for this pressure calculation page?

Here you go:

https://tiresize.com/pressure-calculator/

 

[Miqie]

Here you go:

https://tiresize.com/pressure-calculator/

Thank you!

 

[JED]

Do you have a link for this pressure calculation page?

Yes. Thanks

 

[MT-Taco]

Chalk test

 

[JED]

Chalk test

The chalk test for my 285/75R17 load C Toyo’s found 35 psi front and 32 psi rear COLD. The tires WARM today on an 84 degree day increased 3 psi in all the tires.
So my logic would be to reduce the cold chalk tested pressures by 3 psi in each corner. Does that make sense?
Something never discussed in caulk test procedures I’ve seen.

 

[MT-Taco]

Temps where I live vary wildly -50 to +105! I only adjust my tire pressure a couple of times a year. Set the pressure cold and forget it unless your seeing unusual wear?

 

[JED]

Temps where I live vary wildly -50 to +105! I only adjust my tire pressure a couple of times a year. Set the pressure cold and forget it unless your seeing unusual wear?

Don’t want to get too far in the weeds . The truck ride is improved.

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