Yesterday, I drove 260 miles one way to swap hoods with a guy. Filled up right before I left, got on the freeway, met the guy/swapped hoods, drove back. Light came on about 1/4 home. After my tire size calculation I drove 331 miles on a tank when the light came on! The odometer showed exactly 301 miles. Filled up with 17.8 miles which means 18.5 miles to the gallon. That is with: 6-speed, 35" mud terrains, and a six inch lift. This was 100% highway with cruise set at 64mph...I'm stoked
Actually, may be more. My difference is 13% correct?
from the online tire size calculator
When I used the tire size calculator I think I'm supposed to input 265/70/16's as the stock tire the odometer would have been calibrated to - at least in theory?
When I use the 265's as my base assumption, and the current 285/70/17's the tire size calculator tells me that I'm actually going 6.4% farther than my odometer reads.
If that is all correct, is this the math? (Odometer distance) x (106.4%) = (actual miles). Then (actual miles)/(gallons at fill-up) = (Actual MPG's)?
Is that correct?
My first tank with no correction was 17.2 mpg's on 87 octane.