Odometer error with 265/75/16s

[KingKong8247]

I'm sure this info is out there but I figure this tire is a common size so I'll share my results with everyone.

98 Disco I
265/75/16 BF Goodrich Mud Terrains

I wanted to know my actual mileage versus what the odometer is reading. With larger tires it will read less than actual traveled.

I used a GPS to find the actual mileage.

GPS reading: 15.2 miles (true)
Odometer: 13.7 miles (measured)

To find the percent error you can use the equation [(|true-measured|)/true] *100 which gives me an error of 9.9%. Subtract from 100 and find that my truck is reading 90.1% less than the actual distance traveled.

So to find my actual distance just take the measured odometer reading and divide by .901 which will give me the actual distance traveled. 13.7 / .901 = 15.2

Other tires and trucks may vary but this is one way to find out your actual mileage.



CLIFFS: If you have 265/75 BF Mud terrains divide your odometer reading by .901 to find the actual distance traveled.

 

[brianhoberg]

Bigger tires show less miles while you are actually traveling more. Additionally, bigger tires means you're traveling faster too. Generally, my truck is 3-4mph more than what the spedo says. The odometer trip calculation on my GPS and the trip calculation on the car is generally 10-11% different.
Last tank of gas from full to idiot light was 290 miles on the odometer. On my GPS it was 323 miles. When traveling 65mps on the spedo, my GPS indicates 69mph. Thus, that's why I bought a radar detector too.

 

[adriatic04]

speaking of MPG, after putting new wires (kingsborne) in a week ago or so now, I had a road trip, 70MPH, did 345 miles to idiot light. I was easily doing 285-300 at best prior.

 

[1MITCH1]

I had the opposite problem. My speedo/odo read fast with the stock tires(235/7016) And now with 32's (235/8516) it's almost dead-on.

 

[KyleT]

http://www.miata.net/garage/tirecalc.html

works great