I don't doubt a bit that it can be done, I just am not getting those kinds of results. Those of you that have, have you taken your trucks in for the updated computer programs? I've heard that helps some.

 

I moved from Florida to Tulsa, Oklahoma in the summertime 2002. The weather was quite similar in both places and there is little difference in elevation. The difference in fuel mileage was immediate and quite noticable (roughly 2 mpg in my wife's Subaru WRX and 1 MPG in my old Tahoe). I had three years of gas mileage data to back it up, but I lost it when my HD crashed.

Grim

 

for those that dont have bed covers, try running with your tailgate down or off. this will increase airfllow through the rear of the truck.

To all those that are indicating 20+ MPG, are you just relying on your computer, or are you actually taking the mileage and dividing by exactly how many gallons you're using? Also, have you measured your odometer/trip meter over a 10 mile stretch, using mile markers?

Just curious.

 

About the MPG battle with your tailgate open or closed, here's a website explaining:
http://www.cartalk.com/content/colum...ctober/05.html
Trucks are, in general, designed to get better aerodynamics with the tailgate closed. If you alter your lift or anything on the truck, that can affect it, but generally from stock, just leave it. Now, a toneau cover will be better because it negates that whole area, so no questions there. But when you're talking about up vs. down, you want to keep it up. You get a pocket of air in the bed and any drag is negligible. So your airflow goes from the top of the cab over the top of the bed, then down. If you lower your tailgate, the air goes from the top of your cab all the way down to your truck bed, which is MUCH less aerodynamic.

This has also been discussed here before:
https://www.f150online.com/forums/sh...threadid=43760

 

Ruune, no body will answer that question, it seems to me. My 04 FX4 doesn't have whatever computer tells these folks they are averaging more than 20mpg. I refuse to believe ANYONE gets over 20mpg in an 04 F150. Dividing the miles driven by the number of gallons to FILL UP the tank, tankfull after tankfull, will yield the truth my friends.

Flame on if you want to.........

 

I'm skeptical of the 20+ mpg guys. Assuming it is true, I'm glad I haven't gotten behind you on the road yet because those of you getting 20 mpg have to drive slower than Christmas!

I for one know why I'm only getting around 14 mpg. 1) I only have 2000 miles on my truck and all 2000 miles have came from short trips (60 miles a day) to school and back home. 2) each time I look at my speedo I'm running between 65-70 mph on 2 lane roads and 75-80 on the interstate. Reason for the excessive speed is this truck is so quiet especially with the radio on. I'm trying to watch it closer now because I don't need a speeding ticket.

 

I'm with you.

 

Fuel does matter...

Here in SE wisconsin we use reformulated CRAP gas. However in northern part of the state they do not. I get about 30-40 more miles per tank on the non reformulated gas then the reformulated Crap gas.


Jim

 

My FX4 (5.4 3.73) wouldn't get 20 mpg if I dropped it out of an airplane at 60k feet.

Even when I baby it, the absolute best I've coaxed out of it was 15.2 mpg.

More power to you though bro. Does it ride rough with 80 lbs in the tires?

 

I believe they could get 20 + mpg but only for the very brief moments of the drive that are mostly downhill.

Averages tell me that it will eventually even back out at the 13-16 mpg.

The wife's Explorer has the instant mpg computer and I can get that thing to read 50-99 MPG flat and downhill. BUT, it also reads 5-10 MPG going up hills. It eventually aveages out to the 18-20 MPG mark at the end of the drive.

 

First off good job, but have to ask you what's in your gas. Out here in california besides having horrible gas prices (I paid 2.49 for 87 octane a few days ago) we get the most watered down gas anybody this side of the mississippi. Though on my longer trips that I take to LA and back in the morning from SD I get ~19.6 max.

But my truck is a SCREW with 5.4 3.73 LSD and every option that I could throw at it.

 

I simply don't even try to calculate mine. I know it sucks. I just don't want to know how bad.

 

I guess I agree with some of the comments and not with others, kind of like life itself. Running the "summer" blends of oxygenated fuels that many of the larger metro area stations are required to sell WILL reduce your MPG. On the other hand, running at lower speeds and/or having your bed covered can make a significant difference (although it won't help as much with a Screw as it would on a truck with a longer bed). Headwinds, tailwinds and crosswinds, elevation gains/drops, temperature and humidity can also yield a HUGE difference in MPG. Personally, the best I've ever done with my 04 SCrew 4X4, 3.73, tonneau cover is 18.6 and my average over the first 38 tankfuls is 14.47 MPG. I'm pretty happy with that number.This is always hand calculated for full tanks and is ALWAYS .2 to .4 mpg less than what the computer shows. IMHO, the computer is handy for informing you how you're doing in general, but is never the ultimate way to calculate your mileage.

 

Damn, wish I could get close. I get 12.1 to 12.5 city driving, on the highway 14.0 to 15.4, thats ALL highway too, several different times! FX4 SCrew with 5.4 & 3.73 LS. I must say, I drive on the fast side.

 

n99gt, in answer to your question, that was answered by KJB earlier on this thread, only the Lariats have the onboard trip computer which gives you a running MPG. When you fill it up with gas and divide by the miles, the trip computer is accurate to within +/- .2 MPG of the calculation. About as accurate as your +3-4% error of your odometer, so in answer to your question, the MPG trip computer is as accurate as doing the math at fillups! That being said, on my 04 Lariat Screw 4x2 with 2.5" front lift I get between 14.8 and 15.5 with half city, half highway with some spririted acceleration in rush hour traffic. Again, the trip computer and the calculation have matched very closely. I imagine one could kid themselves into thinking they're getting 20+ by resetting the computer once rolling at highway speed (skipping the gas mileage it took to get you up to speed) and then reading your average before exiting the freeway, thats not REAL life gas mileage, just the average you get coasting along at a preset speed.