Anyone else getting crappy gas mileage in their 2005 4.oL FX4? Plesae post MPG and if better than 12 highway let me know how I can boost mine.

 

Thats pretty bad. You should be around 18-19 if its a stock truck.

Do you have any check engine lights on? I would check air pressure, make sure your air filter is clean, replace the fuel filter, clean the MAF, and run synthetic oil.

Running a can of Seafoam might help some too.

 

x2..... tune up time! Seafoam is a sure fire way to see all the gunk in the engine! I get about 12 city and about 17 highway in my 4.0....

 

Yea, that's pretty bad. 16.7 city, 20+ highway. Go into your profile and make a signature so we know what year you truck is and if anything has been done.

 

I have to agree that pretty bad. I get 16 city low 20's highway and thats on 32x11.5

 

That definitely sounds lows!

On a side note... how often are you guys using Seafoam?

 

I have only done it once, after I bought the truck earlier this year...I plan on an annual treatment.

 

I haven't made any mods just stock ranger 2005 4.0L Automatic. I can go through 1/4 tank of gas round trip to work it is about 46 miles round trip. If I keep it under 60mph I can make a tank last 5 days but it is runnjing on fumes on the trip home on the fifth day. New tires, front brakes, need oil change but thats it.

 

I've never done it but prob will when I hit 100.

 

hole in your gas tank?

 

Any mods to it?

 

wow.something is obvioulsy wrong...............I typically pull 20+ on the highway at 80mph

 

No holes in gas tank just cant figure it out. I have had tune ups fuel treatments oil changes and still i get shtity gas mileage. I dont even think that the sea foam in my tank is doing any good.

 

What RPM's are you turning at 65 mph? Non-FX4 Rangers have 3.55 rear gears allowing 19-21 mpg on the hwy, but the FX4's have 4.10 rear gears. That type of gearing should be good for at least 16-17 on the hwy (especially with stock tires).

 

I just got 21.95 MPG driving to Carlisle for the show--4.0 SOHC/Auto/4.10s/265-75R16s and a performance tune. Something about this combo on my truck just works at 70-75 MPH. I regularly get about 19 MPG driving a mix of city and highway at lower speeds.
Anyway--that's really low; time for plugs, wires, coil pack (maybe), fuel filter, Seafoam thru the vacuum line, check tire pressures, also make sure your brakes aren't dragging.

 

On a quarter tank, I go anywhere from 40-70 miles, and I get at or more then 20mpg most of the time. Are you calculating correctly? Starting with a fuel tank then at next fill up, Miles driven/fuel put in tank