Bigger Tires & Gas Mileage
#12
Just doing that won't recalibrate your speedo. Go have a buddy with GPS or download a free app on your smart phone and check your speedo. You will have to get the dealer to correct the speedo or a custom programer or an off the shelf one like edge or similar.
By the way the only real way to check your MPG is to fill it up write down the miles driven then fill it up again find out how much gallons of gas you put in and divide Miles over Gallons. Looking at some number on your dash with no regard to when you reset it last doesn't matter. Thats just the average MPG calculated by the computer based on your speed, which is probably off and how many miles driven, which is off if you speedo is off.
By the way the only real way to check your MPG is to fill it up write down the miles driven then fill it up again find out how much gallons of gas you put in and divide Miles over Gallons. Looking at some number on your dash with no regard to when you reset it last doesn't matter. Thats just the average MPG calculated by the computer based on your speed, which is probably off and how many miles driven, which is off if you speedo is off.