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Hypothetical for ya guys/gals would a 0.07" variation in tire circumference set off

Happy Hummer

Well-Known Member
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1,455
Location
Wisconsin
Hypothetical for ya guys/gals would a 0.07" variation in tire circumference set off the stabil a trac system or wheel speed sensors?

The AI for google is trying to insist that this would cause catastrophic damage to a H3. Lol! I damn near fell out of my chair. Haha

The rationale I use is that most peeps will at some point have varying psi in each tire which would contribute to a mismatch. I just cant see two HT SL tires being manufactured to the exacting standards that it would take to achieve the level of programing and tire manufacturing lol.

example:

Tire 1#:
Key specifications
  • Size: 265/75R16
  • Load Index: 116 (2756 lbs per tire)
  • Speed Rating: T (up to 118 mph)
  • Overall Diameter: Approximately 31.6 inches
  • Section Width: 265 millimeters
  • Aspect Ratio: 75
  • Rim Diameter: 16 inches
  • Tread Depth: Around 10.5 to 11/32nds of an inch
  • Sidewall: BSW (Black Sidewall)
  • Treadwear Warranty: 50,000 miles
  • UTQG Rating: 500AB (Treadwear 500, Traction A, Temperature B)
  • Tire Type: Highway All-Season
  • 265: The width of the tire in millimeters.
  • 75: The aspect ratio, meaning the tire's sidewall height is 75% of its width.
  • R16: The diameter of the wheel rim in inches.
    31.64 inches×3.1416=99.4331.64 inches cross 3.1416 equals 99.43 inches.
 
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Happy Hummer

Well-Known Member
Messages
1,455
Location
Wisconsin
  • Tire # 2:
    Key specifications
    • Tire Type: All-Season Highway Terrain
    • Overall Diameter: 31.68 inches
    • Section Width: 10.51 inches
    • Load Index: 116S
    • Maximum Load: 2,756 lbs at 44 PSI
    • Maximum Inflation Pressure: 44 PSI
    • Tread Depth: 12/32 inch
    • Sidewall: Outlined White Lettering (OWL)
    • UTQG: 460 A B (Treadwear 460, Traction A, Temperature A)
    • Tire size: 265/75R16
    • Overall Diameter: ~31.7 inches
    • Circumference:
      • C=π×dcap C equals pi cross d
      • C≈3.14159×31.7cap C is approximately equal to 3.14159 cross 31.7
        inches
      • C≈99.58cap C is approximately equal to 99.58
        inches, which rounds to about 99.5 inches


 
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Happy Hummer

Well-Known Member
Messages
1,455
Location
Wisconsin
Question?
How would it be possible that GM engineers could get the h3's software this accurate to be able to tell a 0.07" circumference difference?
Even using 99.43 to 99.58.... that's still 0.15" difference.

How does running these two hypothetical tires with very similar patterns (HT) somehow constitute the death of the 4wd system LOL?
This is a discussion worth having.. as there are many people who will come across this and the silly AI information.

I just cannot get my brain to accept that two very similar HT tire offerings would somehow destroy your H3.
 
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Happy Hummer

Well-Known Member
Messages
1,455
Location
Wisconsin
The axles and the prop shafts would have wear and slop constituting a lot greater than 0.07" variation.

The brake pad wear would be greater concern than this.
And to further discuss both of the dissimilar in this example would then be placed on solid axle back . This would further limit the variation because the solid axle. Slop, age , wear tear in suspension, etc.
 

Happy Hummer

Well-Known Member
Messages
1,455
Location
Wisconsin
Because I'm a stickler for math ...
I keep seeing, hearing 3% variation is acceptable in tire differences between each wheel. Hope I'm getting this ideal correct 😆.
A tire on drivers side is circumference 99.43 and passenger is 99.58 the variance or difference would need to be no greater than 3% of 99.43.
99.43×3% = 2.9829. 99.58x3%=2.9874

Now circumference to diameter with 3% max deviation 😆
A change of 3 inches in circumference is equivalent to a change of approximately 0.955 inches in diameter. Basing this on average size of 265 75 r16. at
99.465 that would mean a deviation of 2.9835 (c) and 0.94967 (d).

So a tire 0.95 inches in variation would be acceptable 😆.
How the h@ll would the original example be a damaging factor. I call b.s.
Google AI and alot of the tire companies are blowing a whole lot of smoke lol.
 

650Hawk

Well-Known Member
Messages
543
Location
SoCal
Alot of the AI I'm seeing is total BS. Worse, when it (the AI) is called out on it, it first doubles down, but eventually admits that it is just making shit up. Sad that so many people think that AI is infallible.
 

Happy Hummer

Well-Known Member
Messages
1,455
Location
Wisconsin
I'm reporting from the front lines 😆 that indeed a Hummer H3 can run a tire/s 0.07" to 0.25" variance between each wheel. My 08 H3 GFB is running 70+ miles per hr.
 
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