moon i

I have a 1999 K1500 Suburban 4x4 with 285/75R16 BF GOODRICH ALL TERRAIN T/A KO tires . what is the best PSI for these tires ? One person told me 35-40 and another person told me 50.

73shark

Welcome to the forum.

Unless they're 6-ply, I'd run about 35 psi. 50 psi probably exceeds the max pressure on the sidewall unless 6-ply.

SWHouston

moon,

It's always better to err on the higher side, than lower.
You'll experience better control, and it's just better for the Tire. I've always noted the Maximum Cold Inflation Pressure, as given on the sidewall of a Tire, and reduced that number by 10%, as the standard operating pressure, regardless of what is stated on the B-Pillar.
When Towing, I'll bring everything, Trailer included, up to the Max Pressures listed, and always air the Spare at that pressure as well.
Right now, I'm running 265/70R-16, General Grabber HTS on my Burb, which are rated at 44psi, and have them at 40.

As our Vehicles age, the information listed on the B-Pillar sometimes gets damaged, and it's not uncommon for the existing size Tires, to be different than the recommended OEM. The decision to make that type change, is often based on price rather than performance, and can make differences in that, as well as Speedometer accuracy.

IF you are running Tires which are other than the OEM size, you can check the difference between them. The Calculator will give you that difference in %, where you can make a mental note of your actual Speed. Take a look at this link...

Tire Difference Calculator:<O</O
http://www.discounttire.com/dtcs/infoTireMath.dos

moon i

Thanks for the info. I will try 45 psi.

SWHouston

moon,

That's reasonable

BFGoodrich All-Terrain T/A KO

PS:
Those look like a pretty darn good set of Tires by the way !
But, those are supposed to be run on 8" wide rims, you know how wide your rims are ?

moon i

I had them mounted on the factory rims. I am not sure how wide they are. NTB installed them. I am getting new rims in the spring and I will make sure they are 8" wide. Thanks for the info.

SWHouston

moon,

Glad to help any way I can, and YES selecting the proper Rim Width is the way to go, few people understand, that you select the Rim Width, according to what width Tire Tread you are going to use. This allows the Sidewalls to be vertical, which is how the Manufacturer intended for them to be used

But, consider one other thing AS you select the new Rims.

There's one other feature, that being what is called "offset".
That's how far the rim is set in over the Brake Assembly. You should measure the distance from your Hub to the inside Bead of your existing rims, and get a general idea of what works for you, and, check how much more room you have beyond that. Getting a Rim that's set in too deeply, may cause scrubbing. However, I'm almost sure that your stock rims aren't 8" wide, so, expect a little inward/negative offset with those new rims, but, not too much though.

HA, I'm inundating you with details ! Most people just throw a set on their ride, and hope for the best. BUT, it feels real good, when you KNOW what you're buying, is a plus, not a negative for performance and piece of mind.

Also, IF you want, I've written a few other Post on Tires and Rims, and you could take a look at them at...

OEM Recommended Tire Diameters: Why a certain Profile and how to select it.<O</O
Post at: https://chevroletforum.com/forum/tahoe-suburban-25/do-20-rims-wide-tires-put-extra-strain-drive-train-etc-tahoe-45721/page2/#post193949
<O</O
Tires and Rims: How a change wider/narrower of a Tire effects performance.<O</O
Post at: https://chevroletforum.com/forum/tahoe-suburban-25/tires-rims-45623/#post193547
<O</O
Changing to Larger Tires using the same Rim:<O</O
Post at: https://chevroletforum.com/forum/general-tech-10/tire-sizes-46146/#post195972