I drive an 06 FX4 with the 4.0SOHC, 5 speed auto, stock 4.10's. The only changes from stock are a T-bar crank, airbox mod, exhaust and 32x11.50's. I'm getting approx 14.04 mpg mix driving. I'm confused since it seems like I got the same mileage on my stock 31's. If someone else wants to do the calculations, be my guest. Trip odo says 229.1 miles and I put 16.312 gallons in. What am I doing wrong, it should be better, shouldn't it?

 

Don't forget to account for the bigger tires. You can't go off the trip odo

 

no that is about what we all seem to get in our trucks. that what i get. your mods you have done to increase your gas milage are pretty offsetted by your tires. also remember that that you milage on your odomite may be a little off since you changes the tire size. i dont know for sure what the difference id +/- on your speed and total distance traveled would be. but im sure its a little different since you have bigger tires and im guess you did not calibrate for them

 

there is a 1.032258 difference in tire height.

so 229.1 x 1.032258 = 236.49 miles traveled

so your getting 14.49mpg lol

 

Thats about right

 

there you go ans thats why i said a little different

 

How long since a fuel filter swap?

 

How the hell do I change it? I have a new one but can't get the old one off. I only have 40k on the truck btw.

 

take off the metal clips or if you have the clips like my 04 you have to get a specail tool to take off those black plactic things...

 

01+ don't require any special tools...

 

tylers 02 needs the tool to release it, but my dads 04 does not. maybe only SOHC's dont need the tool because they are returnless

 

Mine does. its not metal clips

 

huh...idk then. whatev. My brothers '01 2.5L has all the same fittings as my sohc.

 

The black platic ones or metal clips?

 

plastic clips. push with thumb or screw driver on colored tab thingy, pull.

 

I tried that and couldnt get those things off

 

x2, don't wanna budge..

 

Hey for the fuel filter i'm sure its just like my 05. You need the fuel line tool. It is cheap ask for it at a NAPA or local auto store it should be 5 bucks.

To get the filter off, you need to pull the filter off the frame mounting clip.
Then you take the tool... there is two sizes, find the size that the tool closes all the way.

You put the tool on the edge of the fuel filter that is attaching to the hose. the flat size of the tool should be away from the hose.

Next slide the tool towards the fitting fairly hard and yank on the hose slightly at the same time. It takes a little practice to get it off.

Make sure to keep a rag on the filter, and to WEAR SAFETY GOGGLES.

Be sure to relieve fuel pressure by disconnecting fuel intertia switch located inside the truck, and cranking the engine until it does not fire.

Have the other fuel filter near by with caps off... sometimes fuel will want to syphin out still.

It is a messy job, and you will get gas on you and around so make sure you take proper precautions to eliminate fires.

I hope this helps!

 

As for the mileage, I am getting much better mileage than you are and I have just a stock truck with 255/70/R16's and stock everything else. I get 17-18 combined. I get 20-22 highway, and 15-19 local. It depends on my acceleration, if I pass cars fast that drops quick.

Some things you might want to try to improve fuel economy are....

1. Check air filter... Clogged air filter can cause drastic fuel economy changes.
2. Try a fuel additive treatment like Techron.. (note it only treats 12 gallons).
3. Try changing spark plugs and wires, I am about to do this I'm at 65k miles.
4. Change fuel filter.
5. When approaching red lights do not accelerate towards them, coast as much as you can.
6. I have noticed driving over 65MPH drastically kills MPG. 59 on my truck is the sweet spot of 21-23 mpg highway.
7. Leave defroster off, someone once told me this burns gas? I dont know if it is myth or truth).
8. Change fluids in truck, Transfer case, differentals, oil. I do not know how much this will "help" but I noticed that when I changed my diff fluid to Valvoline full synthetic at 50k a 1-2mpg change, almost or I just fixed a problem :).
9. Sythetic fluids I heard once will help with MPG, again this can be argued.
10. Over 55 keep windows closed, use A/C under 55 use windows not A/C.
11. Tire inflation... check it cold, keep it proper, stay on top of balancing too all of which help/hurt fuel economy alot.

I hope this helps. I think it mostly comes down to driving style, drive like a old man, save the $$$ thats what i've done.

 

Well this week I got 16.1 mpg after corrections. I still need to do the air filter and the fuel filter, and I already changed all the fluids except the oil, its not due yet. Tires are at 45 psi, and I doubt it needs plugs and wires at 40,000 miles.

 

Holy cow 45psi. Seems high to me but i could be wrong. I usually run mine at about 32-35. Although i dont think more pressure would hurt mpg as a flat tire is harder to turn that one with more air.

 

Max on the 32's is 50, most shops put in 5 less for expansion. It helps a bit on mileage, less rolling resistance.

 

How do you drive and what do you drive? Are you in the city more than highway? Do you mash it at every stop? Do you shift at 4000 RPM?

If your fuel lines have the colored tabs you do not need tools to get the filter off. Spray WD40 or equivalent in the fitting. Work it around some. Then push the fitting toward the filter then push the clip in with pliers or channel locks then tug the line off. Mine where a pain but they eventually came off.

 

Just a quick reminder to you guys about checking for leaks and loose lines/parts after servicing your trucks..

This happened to my buddies B2 about a month ago, after changing his fuel filter. He's lucky that he got out of it alive. Even lost his pushmower in the back of it..


RIP little Gen1...

GB :)

 

Thank you. I've been easy on it lately, and the mileage is a bit better. Its an auto, shifts at 2500ish. I'm gunna get a 5 speed as soon as I sell my car.