I am want to get more HP and MPG out of my 5.4L. I have new plugs, cleaned the trottle body (thinking about going bigger), CAI w/K & N filter,
2 1/2" SI/SO glasspack muffler and I still get 10MPG.

Help me out guys, what am I missing besides a programmer?

 

I forgot to mention I am also adding an underdrive pully and an E-fan..

 

Wow, 10 mpg's! You keeping your foot out of it? lol!

I have an '06 S-crew with the 5.4L. I did the K&N filter, soft tonneau cover, and Magnaflow dual exhaust and I'm getting 16 mpg city. Up from 13.

 

Actually, it's not my truck, it's a friends truck. I have a quad cab dodge and after all the mods I have done I still get 19 mpg.

He also has a 97 F150 4x4 std. cab which gets 14 mpg.

He drives both vehicles the same, so were trying to c what else we can do to get more out of the S-crew

 

Dang, mine's got a 6" lift and 35's and I'm getting almost 12 mpg's and that's in Hawaii where it's 100% stop-n-go traffic just about everywhere you drive. A programmer will help maybe give you 1-2 mpg's more, but the best way to increase gas mileage is to change driving habits.

 

The tuner, pulley and the e-fans will up the MPG I cant belive you get that low of mpg I towed a 5k trailer and got 14mpg from baltimore to cape cod ma, Ever since I put the Roush supercharger I get 18-20. on the hwy

 

We are going to change the pvc valve as well as the o2 sensor and clean the TB before we add any mods to it...

but keep your suggestions coming guys.

Thanks,

 

It doesn't have a pvc (pcv) valve. I was going to replace mine and was told this by my dealer. The 4.6liter and the V6 still do but not the 5.4 valve in the 2005 model.

As stated above, I learned I can increase my mileage from 13 to 16 in the city by changing the way I drive. Just by being easier on the throttle and slowing down when approaching red lights, trying to prevent stopping. This worked pretty good but I can't stand driving like that.

 

Thanks, I'll make sure I pass that along....

 

on my 04 Screw 5.4 i have an airaid CAI and the edge evo on the extreme setting with everything else stock i get 16.1 city. but i also take it easy on the gas pedal. i use 90+ octane with an octain boost. ido have to admit every once and a while i have to floor it. i love the horsepower!

 

Thanks for all of your help guys. Installed new fuel injectors and now the truck gets 14 city and 17 on the highway. He is still going to add an E-Fan as well as a new throttle body.

He diconnected the battery yesterday to clean the connections and now it dosen't have any throttle reprose... It will crank but it wont move...

The dearler said he needs a programer now....

 

Get a Magnaflow exhaust, and a custom tune.

 

10 is way too low. That would be like flooring it on every take off and stopping way to quick at stops.

If he is driving moderately, even with the foot a little in the pedal, he should still be getting better than that. My 05 gets around 17city w/ no mods, bone stock.

Could possibly be something rotten in denmark, and by denmark I mean his powertrain could be muddled up.

Couple of questions:

Is he using Ethanol free gas? (well as much ethanol free as possible). That "may contain more than 10% ethanol" gas had a bad effect on everything from my SCREW to my lawn mower. If he isnt using "pure gas" he needs to move to it. Its more expensive per gallon, but I guarantee the MPG will end up saving $$.

Could also be a multitude of ooey gooeys in the fuel system. I recommend B&G 44k. I have put that stuff in old clunkers I bought to restore that hadnt ran in years and they fired right up. I also use it after every winter.

No amount of mods is going to cure bad poo.

 

I have a 5.4 supercharged with magnaflow and I still get like 10 mpg city??

 

Never knew of a non supercharged engine to get great economy, but are you tuned? tire pressure high and everything?