Chalk test for tires (1 Viewer)

[Rusty Marlin]

Come to SC and get your free,complimentary pine-pollen chalk test.
In case you're wondering, this is what perfect inflation looks like... The puddle in the top pick is rain water, don't every body panic at once.

And this one is just a touch over inflated, the outer tread blocks are bare of pollen for about a 1/4 of their width.

 

[-Spike-]

Come to SC and get your free,complimentary pine-pollen chalk test.
In case you're wondering, this is what perfect inflation looks like... The puddle in the top pick is rain water, don't every body panic at once.

And this one is just a touch over inflated, the outer tread blocks are bare of pollen for about a 1/4 of their width.

What's the date code on those geriatrics?

 

[1911garand]

What's the date code on those geriatrics?

I remember mounting / balancing hundreds of that old style General Grabber A/T up when I was 16 and a tire tech - circa 1996 - ha!

Right - what is the DOT # on them tires?

 

[Rusty Marlin]

New sneakers are coming in April.
I honestly don't know how old they are. I know the style of tire is no longer available, looked them up. Goodyear Wrangler ArmorTrac

They are a 10 ply trailering tire, they came on it and wear like iron. I was going to replace them when they wore out, but they won't die.

 

[-Spike-]

New sneakers are coming in April.
I honestly don't know how old they are. I know the style of tire is no longer available, looked them up. Goodyear Wrangler ArmorTrac

They are a 10 ply trailering tire, they came on it and wear like iron. I was going to replace them when they wore out, but they won't die.

Ever considered that they may have worn to have full contact at the pressure you run? Do you have a tread depth gauge?

 

[Rusty Marlin]

Depth mics, they are level with in .020 across the lugs at around .1" depth.
Flat enough for me.

 

[COYS]

On my stock body 80 on 37” d load KM3s, I’m down to 26 psi and it’s still not perfectly even.

This is at 28 psi. Is this ok? Many thanks

 

[BILT4ME]

On my stock body 80 on 37” d load KM3s, I’m down to 26 psi and it’s still not perfectly even.

This is at 28 psi. Is this ok? Many thanks

View attachment 2982250

What width rim and what tire are those?

If the rim is too narrow, it doesn't matter how low you go, it won't get flat.

My son's GMC has 6.5" wide rims with BFG 285/75-16 tires. They are way too wide and they "bulge" in the center.

 

[COYS]

What width rim and what tire are those?

If the rim is too narrow, it doesn't matter how low you go, it won't get flat.

My son's GMC has 6.5" wide rims with BFG 285/75-16 tires. They are way too wide and they "bulge" in the center.

9” wide, 12.5 dude. If you’ve never run similar and don’t know it’s A OK

 

[BILT4ME]

9” wide, 12.5 dude

If those are Toyos, they have very stiff sidewalls and may have a tendency to bulge anyway.

Usually, a 12" or 12.5" tire does fine on a 8" or wider rim. 10" is the best.

Years ago, I did a "personal study" of tire pressures, tire wear, gas mileage, and cost of replacing tires vs gas mileage.

This was on a 1995 Jeep GC. Based on high tire pressures so the center was tight and would wear primarily in the center. However, it improved the gas miles 2-3 MPG.

Calculating the cost of a set of tires in 55K miles vs the total cost of gas during that time and an increase in mileage of tire wear, it proved out to be less costly overall of running higher pressure on the tires, shortening their life, improving gas mileage by 2-3 MPG over the life of the tires.

Yes, there is a safety aspect as well, particularly during rain, snow, ice, etc. and you should air down appropriately for those events.

 

[COYS]

Big km3 tires many thanks

 

[COYS]

If those are Toyos, they have very stiff sidewalls and may have a tendency to bulge anyway.

Usually, a 12" or 12.5" tire does fine on a 8" or wider rim. 10" is the best.

Years ago, I did a "personal study" of tire pressures, tire wear, gas mileage, and cost of replacing tires vs gas mileage.

This was on a 1995 Jeep GC. Based on high tire pressures so the center was tight and would wear primarily in the center. However, it improved the gas miles 2-3 MPG.

Calculating the cost of a set of tires in 55K miles vs the total cost of gas during that time and an increase in mileage of tire wear, it proved out to be less costly overall of running higher pressure on the tires, shortening their life, improving gas mileage by 2-3 MPG over the life of the tires.

Yes, there is a safety aspect as well, particularly during rain, snow, ice, etc. and you should air down appropriately for those events.

Drove a bit on hwy and local roads at 26 psi and it just didn't feel right. Still got to 80 mph cruising speed without fuss, but the driving sensation was just a bit too soft/numb.

Even at 26 psi cold, the center was still light on chalk compared to the edges. The KM3s have a very rounded design compared to the K02s or comparable AT tire so per your logic/calc, I bumped it back up to 32 psi cold and it shall remain there.

Thanks, again, BILT.