Anyone know which gear will get me close to being accurate? Thank you!

either with GPS or the mile markers on the interstate (go 5 miles) see what percentage of error (either too fast or too slow) your ODO is showing. 6% too fast needs 6% more teeth than you have now (& vice versa). this will get your ODO correct then if the speedo ain't right it will need to come out & go to a speedometer specialty shop to be recalibrated but your odds are good if you get the right teeth to get the ODO correct that the speedo will (also) be correct. OR if it is off & mileage is more important than MPH you can select proper teeth to get the ODO in line & just be aware that the speedo is however much too fast or too slow. A stretch, but tossing that out there for your info. I did do "rollout" in a parking lot then divided by Pi for actual tire dia then went to the MP chart for dia/gear ratio for the teeth count selection & it was dead on

I have a handy chart that will tell you but I cant post it because it's in word and not a .jpeg or the other assortments. If someone what the ability to convert will PM me their e-mail address I can send it to them to post. The chart shows a 31 tooth for a 28" tall tire (which most 275/60s are) and a 3.23.

There are a number of great phone apps that work very well and some are free. Google speedometer apps.

I use one called 'speedometer',,,of all things. Excellent.

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