Look at what they have done with the intakes on the F-150's. They are all going towards the concept of a CAI. Get the air from the outside, not the air from inside the engine compartment. The motor companies must think that some of these things are working.

 

Maybe try a lowering kit, there not too expensive. Seeing as how you are trying to move an object with the arodynamics of a brick you want to create as small of a surface as posible.

 

Your best mileage without a lot of extra investment in replaceing parts is to run harder tires in the 45 lb range.
Get in the habit of driving with a light foot trained to back off the throttle after cresting a hill and catching yourself with throttle applications when it's not needed (actually a bad habbit) of everyone.
Stay below 65 mph.
Use the reccomended 5w20 oil, keep the injectors clean with additive once in a while as added insurance and try to use gas with no Ethanol.
Replace plugs more often and using the lesser grade ones will get you better performance "more of the time" instead of waiting so long that you see a performance drop that has been using more fuel before you begin to see it.
Any money invested in parts unless you know they are needed is a waist in practical terms of dollars vs the gas you would burn.

 

Bluegrass...what you say makes a lot of sense. Modern auto companies do all they can to get good mileage...especially for F-150s because of the poor mileage rap.

I spent a lot of $$ on my Chebby 4WD 350ci and got improvements in different torque ranges...but not particularly better for all around driving. I chipped my '85 928 Porsche and got gains...but in my '88 S4 it's not worth wasting your money since the car companies had better technology in '88 than in '85. I'm assuming that the basic engineering behind my2006 F-150 is even better.

Again, Bluegrass' suggestions will give the most mpg gains at less cost. However, the expensive mods others have suggested may alter the torque curve for F150s. Gearing would probably do more if you're looking for highway mileage rather than towing, etc.

Just my 1.50 cents.

hh928

 

I swapped out all fluids, except the tranny, with synthetic and saw an average of 1 mpg gain on the '99 4x4. I drive mostly short trips, work commute is 4 miles, and fairly aggressively.

The rear diff came with synth and I was already running Mobil 1 so I swapped the front diff, transfer and power steering. This was on a truck that had 95K miles at the time of the swap. I was gonna do the tranny but I found out I'd be buying the dad-in-law's '05 when he got his '09 so I decided to save a bunch on the synth Mercon.

The p/s pump was whining a lot before I switched to synth, it ran quiet afterwards. When I sold the truck it had 128K miles on it. Mileage was the same and p/s pump was still quiet.

 

something to keep in mind with all of this CAI and exhaust talk...

If you increase the amount of air that an engine can ingest and exhaust, it injects more fuel as well. The only time increasing airflow will increase MPG is if the modifications increase combustion efficiency MORE than they increase airflow.

If you end up using less pedal to achieve cruise, it has to be a greater change than the increase in air density/mass that you've introduced to the engine in order for it to increase MPG.

... and I don't know about you guys... but when I put on an intake and exhaust, I like to HEAR it, so my MPG goes in the can.