1” diameter worth worrying about odometer or speedometer?

[Jeepnoob34]

I’m considering upgrading stock overland tire to some KO2’s that are 33’s. Keeping the same wheel. So it’s only around 1” difference. Should I be worrying about gearing, speed, or odometer issues with only a 1” difference? Feel like I’m overthinking this lol.

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[Discount Tire]

The gearing should be fine You can check the difference in the speedometer at the link below:

Tire Size Calculator | Discount Tire

Please let us know if we can help.

 

[robburns76]

i went up almost an inch from the stock sport s tires to overland and my speedo is off by about 2mph.

 

[Bbannongmu]

I’m considering upgrading stock overland tire to some KO2’s that are 33’s. Keeping the same wheel. So it’s only around 1” difference. Should I be worrying about gearing, speed, or odometer issues with only a 1” difference? Feel like I’m overthinking this lol.

You’ll have no real issues from that small increase. My advice - Just Do It!

 

[PyrPatriot]

My advice: dont do it. Change may be small but it adds up over tens of thousands of miles and when you sign that document stating the odometer is correct you commit fraud (at sale of Jeep)

 

[Renegade]

My advice: dont do it. Change may be small but it adds up over tens of thousands of miles and when you sign that document stating the odometer is correct you commit fraud (at sale of Jeep)

Please!!! You don’t even know that it not still within the factory margin of error. We’ve been through this....
It has be be measured to see.

 

[PyrPatriot]

Please!!! You don’t even know that it not still within the factory margin of error. We’ve been through this....
It has be be measured to see.

But I WOULD know there is a likelihood of it being off. On my personal conscious I wouldnt do it. Half an inch, or an inch for special outings, sure. But not for the lifetime of the vehicle without recalibration

 

[Jeepnoob34]

But I WOULD know there is a likelihood of it being off. On my personal conscious I wouldnt do it. Half an inch, or an inch for special outings, sure. But not for the lifetime of the vehicle without recalibration

Thanks for the input guys. I’ll think it over.

 

[Renegade]

But I WOULD know there is a likelihood of it being off. On my personal conscious I wouldnt do it. Half an inch, or an inch for special outings, sure. But not for the lifetime of the vehicle without recalibration

If the factory speedometer/odometer margin of error is present, maybe you should have that on you conscious when you sell it. My point is, and has been, that if it’s accurate after measuring, its freaking accurate. There is no odometer discrepancy. Most factory odometers/speedometers read higher than actual speed...

 

[PyrPatriot]

If the factory speedometer/odometer margin of error is present, maybe you should have that on you conscious when you sell it. My point is, and has been, that if it’s accurate after measuring, its freaking accurate. There is no odometer discrepancy. Most factory odometers/speedometers read higher than actual speed...

we will just have to disagree. You may see it from a practicality perspective, I see it from a contract language perspective and interpretation of my state’s statute. For me, if I put on larger tires that will change the rotational circumference and even if it is within some imaginary margin of error it is still a volitional act on my part that changes the odometer from what it would have been had i left things factory.

 

[PyrPatriot]

https://www.caranddriver.com/features/a15136801/speedometer-scandal/

This is for speedometers

In the U.S., manufacturers voluntarily follow the standard set by the Society of Automotive Engineers, J1226, which is pretty lax. To begin with, manufacturers are afforded the latitude to aim for within plus-or-minus two percent of absolute accuracy or to introduce bias to read high on a sliding scale of from minus-one to plus-three percent at low speeds to zero to plus-four percent above 55 mph. And those percentages are not of actual speed but rather a percentage of the total speed range indicated on the dial. So the four-percent allowable range on an 85-mph speedometer is 3.4 mph, and the acceptable range on a 150-mph speedometer is 6.0 mph

5% over 100k miles is 5000 miles, which moves the value factors for re-sale above the 100k if say you are selling it as “below 100k mi”

 

[Renegade]

https://www.caranddriver.com/features/a15136801/speedometer-scandal/

This is for speedometers

In the U.S., manufacturers voluntarily follow the standard set by the Society of Automotive Engineers, J1226, which is pretty lax. To begin with, manufacturers are afforded the latitude to aim for within plus-or-minus two percent of absolute accuracy or to introduce bias to read high on a sliding scale of from minus-one to plus-three percent at low speeds to zero to plus-four percent above 55 mph. And those percentages are not of actual speed but rather a percentage of the total speed range indicated on the dial. So the four-percent allowable range on an 85-mph speedometer is 3.4 mph, and the acceptable range on a 150-mph speedometer is 6.0 mph

5% over 100k miles is 5000 miles, which moves the value factors for re-sale above the 100k if say you are selling it as “below 100k mi”

Good grief man, I’m saying that if you measure (with gps, radar, stopwatch, or otherwise) the speed after changing tires, and the speedometer proves to be accurate, there is no moral, legal, or other issue. It’s damn accurate.

 

[WXman]

I’m considering upgrading stock overland tire to some KO2’s that are 33’s. Keeping the same wheel. So it’s only around 1” difference. Should I be worrying about gearing, speed, or odometer issues with only a 1” difference? Feel like I’m overthinking this lol.

For me personally, I wouldn't. Going from Sport tires to Rubicon tires is a 3.87% change. (And yes, I've done real world measurements myself.) I need more change than that to be concerned about it. But, everybody is different. I'd leave it alone and roll on!

For what it's worth, I've seen inaccuracy in speedo/odo readings on vehicles right off the assembly line. So, again, small changes are no big deal. Larger changes....yes that's a different issue.

 

[Hipbilly]

I went to 285/70/17 BFG TA/KO2. I did not take a "before" measurement, but cruising at 80mph, my GPS read 82.7mph.
My decision, for my truck, was that's not enough to worry about.

 

[mzeblue]

I’m considering upgrading stock overland tire to some KO2’s that are 33’s. Keeping the same wheel. So it’s only around 1” difference. Should I be worrying about gearing, speed, or odometer issues with only a 1” difference? Feel like I’m overthinking this lol.

For several hundred dollars, the Mini Taser is well worth the price just for the ability to disable that annoying auto shutoff. And, you gain the ability to adjust your speedometer for tire changes, among other things. I use the visual speeding warnings in Waze, especially when the speed limit changes below my cruising speed, so for that reason I like having my speedometer reading as accurately as possible.

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