[McMilly]

I Purchased a new 2013 FX4 about 5 weeks ago. I have 2,200 miles on it. I have 2 questions:

#1 The sticker from the window says it has a 36 gallon tank. I have run it nearly empty twice now. By empty I mean all the way down on the guage, the fuel light comes on, and the comp says I have less than 100 miles to empty. Both times the tank took just under 30 gallons. I thought ford had a 26 and 36 gallon option. Is there a 30? Is the truck just saying I am empty when in fact I have a 5 gallon "reserve"????

#2 My friend bought almost the exact same truck. The only differences: I have the 3.73 he has the 3.55. His is all stock while I have an AFE stage 2 CAI with the Borla touring twin exhausted straight back. We went to AZ for spring training. We were traveling between 70-80 mph the whole way. I averaged 18 MPG and he got 19.6 MPG. It is the 3.73 or the CAI causing that much difference in MPG??

I really appreciate all the wisdom on here with these trucks.

 

[Stage3Motorsports]

on question #2: Do you both have the same wheel/ tire package? That can make a big difference.

 

[RubyTues]

Here's my $.02:

1. Apparently, you were not very "nearly" empty but do have a 36 gallon tank. I've run my '13 about 15 miles beyond "0 miles to empty" and it would only take 25 gallons.

2. Assuming your tires are the same, the different rear ends will make some difference. So will intake and exhaust but so will aerodynamics. Was one of you following the other? A/C on? Windows down? Does one have a heavier foot? There are plenty of variables.

 

[1fastbob]

I Purchased a new 2013 FX4 about 5 weeks ago. I have 2,200 miles on it. I have 2 questions:

#1 The sticker from the window says it has a 36 gallon tank. I have run it nearly empty twice now. By empty I mean all the way down on the guage, the fuel light comes on, and the comp says I have less than 100 miles to empty. Both times the tank took just under 30 gallons. I thought ford had a 26 and 36 gallon option. Is there a 30? Is the truck just saying I am empty when in fact I have a 5 gallon "reserve"????

#2 My friend bought almost the exact same truck. The only differences: I have the 3.73 he has the 3.55. His is all stock while I have an AFE stage 2 CAI with the Borla touring twin exhausted straight back. We went to AZ for spring training. We were traveling between 70-80 mph the whole way. I averaged 18 MPG and he got 19.6 MPG. It is the 3.73 or the CAI causing that much difference in MPG??

I really appreciate all the wisdom on here with these trucks.

Were the mpgs hand calculated or based of the silly computer readout? The computer mpg readings will vary quite a bit.

 

[McMilly]

Computer readings for info

 

[McMilly]

See this is why I love this forum. I have the FX appearance package so I am pretty sure the tire size is different (the rims are for sure). We both were using CC but I did have a rack on the back with a bike and my smoker tide to it. A little more drag than his for sure. I guess it is starting to make sense about lower MPG from the on dash computer. I need to get a tune anyways!!

The gas tank thing is still weird. Guess I'll have to monitor that. Don't like going below half a tank anyways since it takes two swipes of card to fill up here in CA.

Thanks again.

 

[btswein]

They build a few extra gallons onto the computer to trigger the fuel light so you don't get stranded. This was about 3 gallons on my previous ride.

 

[mwhals]

On mine, I usually take 30 gallons to fill it when 100 miles are left on the "miles remaining" estimate.

 

[darrendeatz]

I have a 2013 Lariat SCrew, also bought very recently, only about 1600 miles. Last time I filled up, the comp said I had 25 miles to empty and I put in 32 Gal. Another time, I put in 31. As for #2, Bill is right about the tire package, or any modifications you make that affect rolling resistance (road friction, wind, etc.) I was getting around 19 on the road as stock, but then I added a bully bar, step bars, a tonneau cover and WeatherGuard Mudflaps, all of which may have a cumulative negative effect on MPG. Also, I added 2" wheels spacers to set those 20s out to the outside of the body as well as a 2 1/2" leveling kit to the front suspension. Those two mods may have also had an effect on resistance.

Now, about the best I can do on the highway is 15. That's dissappointing. In fact, I think I get better city mileage than Highway. I do better on local roads where I'm around 55MPH and not using CC.

I just ordered 3 items from Stage3Motorsports with the hopes of improving my economy:
aFe Stage 2 Cold Air Intake (Pro Guard 7)
aFe Bladerunner Charge Pipe
AFE Mach Force XP 4 Inch Cat Back Exhaust

Once I get them (very slow order processing), I'll report back on any gains. I can't decide if I should install them one at a time, then run out a tank to test mileage or just put them all on. Did you notice any gains (MPG or Power) with your upgrades?

 

[sstroud]

If it said you were just under a 100miles to empty and you filled it with 30 gallons, avg 18mpg that'd leave 5gallons + 1 gallon reserve. 18*5 = 90.

Vehicles don't calculate reserve into DTE. I was driving a 2013 sentra for a while, 13.75gal tank. LFW light came on at 9.5gal every time. I could literally go 150miles on E.

 

[wpizzi]

I usually fill mine up at quarter tank of gas and on average 26-28 gallons to fill it. I have ran mine down to 7 miles till empty and it took 33 gallons to fill.

 

[spence08]

Ran mine to zero to change to a different octane tune. Almost 35 gallons to fill it