Wondering if the odometer captures mileage with a mechanical reader or with something off the GPS? In older trucks, we had that cable attached to the drive shaft or end gear in the transmission. T...
I believe they still go off of some sort of tire rotation. If you changed your tires, in order to be accurate, you will need to have your speedo recalibrated.
Pull out a GPS and check your speed on the highway. I bet it is now off.