hope you guys can help me? you guys seem to know the most about mods. i have a 98 f150 with lightning wheels on it i just put 4.10's on it and my speedo is 10 mph off. at 65 im actually doing 55. i have the anolog mile reader. what speedo gear do i need to correct this? or do i need to go to the dealer and get the computer flashed?

 

ringmaster: I d/k the answer to your ? but this will bring it back ttt. We get our speedos corrected with our chips............

Dan