Speedometer/odometer question

hey guys... question for ya...

so, changing tire size affects the correct reading of the speedometer. the larger the tire, the faster you are going compared to what the speedometer shows. for me, i went about 3% larger on the tires and this brought my actual speed in line with what the speedometer shows (verified with GPS). for larger differences, i know there is the calibrator that you can buy to correct the speedometer reading.

however, what about the odometer? for me, since the speedometer is now correct, would the odometer also be correct? or would i need to add in 3% additional miles to what the odometer shows?

thanks,

 

My DC did the same. According to GPS, I was going 2mph slower than what speedo was showing on stock tires. Bumped up to 33", now my speedo and GPS are spot on. Logically, I would assume the odo and speedo are calibrated to each other to prevent any discrepancies.

That's a good question though..I'll have to check that out on the way home.

 

so, are you saying that my odometer should be correct now?

 

wait... in my example, i did not use a calibrator. with the larger tires, the speedo just happens to be correct now. would the odometer be correct as well?

i guess a better question would be.. does the speedometer and the odometer use the same readings for their calculations? and if the calculations for one gauge changes, will the calculations for the other gauge change as well?

 

Yes you're correct. They coincide with each other. If you're speedometer used to say 2 miles an hour slower than what gps said that means that in one hour going 60 mph you thought you went 60 miles in reality you only went 58. Your odometer will think the same way.