Plug-in Tuners '09 Explorer 4.0
 

Good morning, does anyone have advice on alternate tunings for an '09 4.0 2WD Explorer? It sounds as though I have detonation very frequently at speed and the mileage is only 15.6. The '99 I had previous to this Explorer typically got over 19mpg. It's a good vehicle, just not as economical as I had hoped. Thank you in advance for your response!