2005 Ford Explorer fuel economy dropped

my gas economy went frrom 18MPG to 12MPG is there an explanation for this ,what can I do to solve this.

my car is 90,000mi

Bad thermostat is my first guess. Watch the coolant temp gauge and make sure it quickly moves to the center of the range when the car is started cold each morning. If it doesn’t than there is your problem.

Have you changed driving habits recently or started to drive a different route that is more city less highway? Have you made any repairs recently? Changed tires? Are they properly inflated to specified PSI? I doubt winter blend gas is out this early, but that will compromise gas mileage a little bit…major change in ambient temperature?

Also, cooler weather hurts economy and drops tire pressures which further hurts fuel economy.

This truck is rated at 13 MPG in the city, 12 MPG is not a difficult accomplishment. I have had to deal with many new vehicle owners that had below EPA rating driving conditions.