Just put on larger wheels and tires. Is there a way to calibrate the speedometer?
 

I went from 205/75 14 to 215/70 15.
Any calibration needed?

Thanks, T

The dealer can change your pinion factor in the transmission controller. If that size isn't on the list they can get you closer anyway.

The rule of thumb I've always heard was that you could go one size wider if you went down a size in aspect ratio which is what you have done. I went from 215/65/17 to 225/60/17 on our 2001 and the speedometer was perfect when I checked it over a 10 miles stretch of interstate.