If you are in the United States you cannot change the speedometer on the Mazda 3 from miles to kilometers. The only option available is miles.
The over-all size of the tire and wheel would change the calibration of the speedometer/odometer.
Every 70000 miles or 7 years, whichever occurs first - Citreon recommendation
To change the speedometer of a Mazda RX-8 from miles to kilometers, start by turning on the ignition without starting the engine. Then, press and hold the trip odometer reset button located on the instrument cluster. While holding the button, turn the ignition off and then back on, continuing to hold the button until the display changes from miles to kilometers. Release the button, and the speedometer should now reflect kilometers.
The 2.4l does, change at 100,000 miles.
The grand prix has an electronic speedometer that can be set to read-out in miles per hour or kilometres per hour, the red mph means its currently set to read miles per hour
on my 2002 1.6i petrol version it is 70000 miles or 10 years, what ever is first.
150,000miles. Se the maintenance guide
Hold the bottom left button as you turn on the key.
what you see when you look at the speedometer is the average distance you have traveled. notice the speedometer says mph Miles Per Hour how many miles you have traveled per hour.
Then it is time to get it fixed.
trumpeter miles davis