Larger Tires = better MPG & more miles than Odometer

[Stevenc150]

[This only applies if u have NOT calibrated your truck Odo. to New, larger-than-stock diameter tires]

I put 285/55/22 RG on awhile back. Using GPS i knew i gained around 5mph...which meant my MPG should also be up. But truck mpg readout & my calculations both showed a drop

I knew: [larger diam tire] = [bigger circumference] = [each tire revolution I traveled further] = my MPG should get better!​

Then it occured to me...that meant my Odometer reading would be off too!! So using Discount Tire's tire comparison tool [thumbnail]...I now add 7% to the mileage side of the calculation, netting an MPG gain. (Or just figure MPG per normal, and add 7% of that back onto it)

[Example using 350 miles on odometer reading...]
Previously: 285/45/R22 = 350/25gal=14mpg
New: 285/55/R22 = 375/25gal=15mpg

P.S. This also means a 10K oil change is actually a 10,700 oil change

 

[Richard320]

Yes, but you also will want to get things calibrated, because it affects more than just speedometer and odometer. Transmission lockup and shift points, Antilock brakes, traction control, all kinds of stuff depend on wheel speed sensors.

 

[Stevenc150]

Yes, but you also will want to get things calibrated, because it affects more than just speedometer and odometer. Transmission lockup and shift points, Antilock brakes, traction control, all kinds of stuff depend on wheel speed sensors.

True, but 7in distance traveled is the variance, I dont see that causing an issue with ur points. MPH & MPG is the greatest disparity as 7in / per rev. in a mile really adds up.

Besides if there were issues stemming from larger tires beyond the OP, I'm sure there'd be threads up everywhere as to the necessity to calibrate as it's maybe the most popular mod out there. Either way those are good points that I hadn't considered

 

[Glenn141]

[This only applies if u have NOT calibrated your truck Odo. to New, larger-than-stock diameter tires]

I put 285/55/22 RG on awhile back. Using GPS i knew i gained around 5mph...which meant my MPG should also be up. But truck mpg readout & my calculations both showed a drop

I knew: [larger diam tire] = [bigger circumference] = [each tire revolution I traveled further] = my MPG should get better!​

Then it occured to me...that meant my Odometer reading would be off too!! So using Discount Tire's tire comparison tool [thumbnail]...I now add 7% to the mileage side of the calculation, netting an MPG gain. (Or just figure MPG per normal, and add 7% of that back onto it)

[Example using 350 miles on odometer reading...]
Previously: 285/45/R22 = 350/25gal=14mpg
New: 285/55/R22 = 375/25gal=15mpg

P.S. This also means a 10K oil change is actually a 10,700 oil change

View attachment 57620

you should take into account the weight f your new tires as heavier tires will affect mileage in a negative way.