I use my GPS to tell me the correct speed. The speedometer is almost 5 mph off at freeway speeds.
If you really want a speedo that is telling you the truth, look into getting a speedometer calibrator. I will be getting a Dakota Digital unit at my next service when they change the air filter.
The calibrator has 2 buttons for bumping the unit up or down in fractions of a MPH. Easy enough to re-calibrate as the rear tire wears smaller.
This allows me to run the tire that fits and functions the way I want.
If you go to a larger diameter tire to correct the speedo, the calibration will change as the tire wears down. Probably not enough to make a big difference, but it will.
The larger diameter tire will also change your overall gearing. It will reduce your freeway RPMs by approximately 250 to 300. It's a pleasant little change but barely noticable.
Besides the freeway performance, if you tow a trailer, you will also notice a slight difference when you take off from a full stop. A little bit more slipping of the clutch is required.
So, you all have to make the decision as to what you like best. I have made mine for me.
JMO
:agree: