I have a 2003 F150 Screw 2WD lifted 3 inches and I'm averaging like 11.6 mpg...would a tuner be the right way to get a little bit better? I was checking this one out online and just would like suggestions

 

Not really. You'd be driving quite a while trying get the measly MPG savings to even break even on the cost of the tuner AND the tune you'd need.

 

Edit: He's not listening anyway .

 

You will not get enough (if any) mpg improvements to cover the cost of the tune and tuner.
You get a lift and larger tires you will get lower MPG. Regearing may help a little, but again, the cost will probably never be made up with the minimal MPG improvements.
Driving style is the best improvement in MPG (and cheapest). Slow acceleration (keep RPM's below 2000), steady speeds, slow appropriately at stoplights etc.
A tuner will allow you to adjust the speedometer for larger tire size so that way you can be sure you are getting an accurate MPG reading.
Although 11.6 MPH is not out of the normal range for these trucks.

 

Did you change the tire size and not correct the speedometer? This is make you mileage read lower/higher, when you may be getting better or worse depending on how far off it is and your driving traits. If you didn't calibrate the tires to speed, then your mpg is off anyways.

 

A lift kit alone can hurt your mpgs some.

 

I haven't changed the tires I got 255/70R16

 

Would a programmer help?

 

Well that ruled out that thought.