I need better fuel mileage from my '04.... suggestions?

[Stangman]

Hi all,

This may be a dumb or rhetorical question considering what my truck is..... but is there anything I can do to get my '04 FX4 level2 in to the low-mid 20mpg range??

I LOVE my truck.... but its eating me alive on fuel costs.

I've already got a K&N filter (like that's a huge difference lol) and the rest of the truck is stock. I do plan to put a catback exhaust system on it as well in the future. But is there any other proven methods that will help me? I drive 100+ miles per day most days just in an average week I will put 5-700 miles on my truck. Maybe more!

A friend had told me to do a manual hub conversion, but I don't really know all of what that will entail... and I don't wanna get rid of my Alcoa's.

Hopefully you all can help me.... I don't want to trade it in for an econobox.... I use this thing too much!

Thanks for looking!

Jesse

 

[koda6966]

It's allll about how you drive. I had a 3.0 that could barely manage 20 on a good day. My brother has a 2002 3.0 and that's about all he gets too.

If you need mileage, pick up an older car for cheap just to drive to work and beat around in. A 90's Probe can look slick with the right touches.

 

[Stangman]

Well, I need to get rid of vehicles not add more. Lol

 

[bigtruck94]

Add a cold air intake to it. I'm pretty sure there are companies such as AFE power make some kits for them. I made a custom one for my 94 and it increased gas milage and add a few horses to my 4.0l. Like you said, A cat back exhaust could give you an extra 1-2 mpg and make your truck sound really good. MBRP makes some really good exhaust!

 

[basketranger]

being a northerner an e-fan may not be as much of an improvement as I found, but is an option. the other item is Fitch Fuel Catalyst, I picked up on average 1.3 mpg

 

[adsm08]

Go downhill more.

 

[gw33gp]

I can only get over 20 mpg highway mileage when I keep it under 70 mph and be easy on the accelerator pedal in general. The only mod I have done that actually improved gas mileage was a reflash on the computer. The other stuff made it sound better and may have provided a slight increase in power but did nothing for gas mileage.

Manual hubs will give you less than .5 mpg gain but every little bit helps. I considered doing it until I fund out how much it would cost to do it. I know of someone with an 03 FX4 LII that did it and he says he if he had it to do all over again, he would not do it.

 

[RonD]

Put lifts in the back of the truck so you are going downhill all the time

Make sure your engine is getting up to normal temp range ASAP, you should have a stock 192deg or 195deg thermostat, coolant between 200 and 220deg will give you the best MPG, also the best lubrication, running cooler kills MPG.
Normal warm up should be within 5 minutes, if it takes longer then t-stat may not be closing all the way when cold.
When engine is cold the computer runs the engine rich, just like a choke did, and it doesn't use the O2 sensors to set best MPG, this is called "Open Loop", once engine gets warmed up the computer switches to "Closed Loop" and uses the sensors to set air/fuel.
O2 sensors are like spark plugs in some respects, they do wear out, at what point is still a debate, lol, but they do set your air/fuel mix so if they are off by a little you could be running richer than needed.
You can test O2 sensors.

Auto hubs should be disengaged when not in 4x4 mode so that shouldn't effect MPG.

Weight is a big factor along with aerodynamics, you can't change the body design easily but you can lessen the weight if you are carrying things that are not needed for the commute.

You can get an OBDII plug-in gauge that will give you instant readings on best RPM and speed for best MPG.
Ultragauge is an example of one that does that, at $70 it might pay for itself in a few months.

 

[Lil-Pony]

e fan gave me a .5-1mpg improvement but im in the south.