Recalibrating the Speedometer

[deathsquadd]

I am going to be switching from a P235/75R15 to a P245/75R16. Reason being is I want to use wheels from a 2002 Ford Ranger. What is the procedure for recalibrating a speedometer for a 1992 Explorer XLT? Right now there are stock size tires (P235/75R15's) and the speedometer reads 5mph faster than actual speed. Any help is appreciated.

 

[Tbars4]

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