I need better MPG. I have a 04 F-250 6.0L its getting a avg of 14.8mpg. So i put a Bully dog intake and didn't help, still at 14.8. I used a bottle of Sea foam still no help and cleaned of the MAF. The truck only has a intake. Any ideas?

 

I was getting about the same mileage with my 04 6 liter as well. I got the quadzilla max mileage module and now have been getting constant 17 to 19 mpg. Well worth the money in my opinion!

 

Driving slower and long coasts to stop signs are always a good idea.(saves on the brakes, too) I get way better mileage when I'm not in a hurry.

I'm not 100% sure this makes a difference in trucks this big, but on my other vehicles, I found that highway tread tires on aluminum rims helped a little. Again, I'm not sure how much difference a little unsprung weight on a 7700 lb truck makes. Thankfully, someone around here will know.

 

Forget programmers. 99% of mileage improvement is in your right foot.

1. Our trucks are as aerodynamic as brick walls. Since the coefficient of drag squares (not cubes as someone else posted) with doubling of speed, you need to keep your MPH down on the highway. In other words, a lot of your horsepower and fuel is spent pushing air. Going faster takes disproportionally more horsepower.

For example: The Bugatti Veyon produces 1,001 horsepower to achieve 253.52 MPH.

The Bugatti Yeyron Super Sport can travel at 267.85 MPH but needs 1,200 horespower.

That's 200 more horsepower for just 14.33 extra MPH and most of it is used to move air out of the way.

2. Pump up your tires to pressures closer to the numbers posted on your door jamb to reduce rolling resistance. A lot of guys run tire pressures in the low 50s unloaded which is perfectly O.K. as far as tire loading, but not optimum for mileage. Ford says my 2005 Powerstroke single cab FX4 with 245/75 17 tires should be at 70 psi front and 80 psi rear. Obviously, those pressures are for a fully loaded truck towing maximum loads. I run about 65 psi front and 60 psi rear when empty.

3. Take the junk out of your truck. Most of the guys I know carry about 400 lbs. of junk they never use in their trucks. If you don't need it, you don't need to waste extra fuel moving it around.

4. Buy a Scan gauge II and set it up to show instant MPG and the average tank MPG (average MPG between fill ups). You'll soon learn how much fuel you waste by pushing the accelerator down an extra 1/4" and what happens to your average MPG with just one 0-80 MPH blast. MAKE SURE YOU GO THROUGH THE CALIBRATION PROCEDURE.

5. If you have a lift and/or big tires, go back to stock.

6. Watching the Scan gauge, I average about 15.5 MPG in town (that's Cody, Wyoming, not stuck in traffic on the 405 in Los Angeles) and about 19 MPG on the open highway (no traffic in Wyoming). That's empty driving in fuel saving mode and keeping it between 62 and 65 MPH on the highway.

 

The dealer I bought my 2005 XL from showed me a letter from Ford Motor Company informing him that installing big wheels and tires on new trucks affects acceleration, handling and stopping. It strongly advised that dealers shouldn't equip new trucks with big wheels and tires prior to delivery.

A few years ago, Car and Driver took an SUV (Escalade I think) and tested acceleration, handling and stopping with stock wheels and tires followed by 20s or 22s. There was a significant difference in all three areas..

I'll try and find the article.

The Australian version of Top Gear tested a Walkinshaw modified HSV Clubsport (Monaro - the new Pontiac GTO). with the Stig driving, it did a 1:13.60 lap of the test track with standard 18" wheels. They ran another lap with optional 22s and the time dropped to 1:15.19.

1.6 seconds is an eternity on that short track, all due to heavier wheels/tires.


Don't forget, it's not just more unsprung weight. It's increased rotational weight. You've got to get those heavier wheels/tire moving (spinning), you have to stop them, too. Plus, once they're spinning, they are effectively gyroscopes and resist any change of direction when you turn the wheel. (Ever take a bicycle wheel, hold it by the axle and spin it, then try to change its orientation?)

 

I found this article about upsizing wheels on a VW, still looking for the SUV blurb.

Effects of Upsized Wheels and Tires Tested - Tech Dept. - Auto Reviews - Car and Driver

 

Exactly...if you wanted fuel mileage, should have bought a Focus. Now to get better mileage out of the SD, speed kills mileage. The best mileage I saw out of my truck repetitively was when I keep the speed at 60 mph (two-lane highway). I was getting 21-22 pretty much every tank....hand calculated. The 4WD/FX4 guys maybe able to go more places, and move around easier when the white stuff is on the ground...they also have to pay the piper when it comes to mileage. All that extra weight for the transfer case, front drive line, front axle/hubs all add extra weight; and in the case of the front axle...more drag. I run my tires (highway Michinlin) at 60 psi on all four corners; oil change every 5k, fuel filter at every 10k and I slow roll it off every stop light/sign and slow roll up to them all. With 3.73LS in the pumpkin as long as I keep the truck below 70 mph (2k on the tach) on the highway I get 18-19 on the interstate. I'm not saying you can't get any better mileage than high-teens/low twenties...but unless your going to draft off a 18-wheeler, there's only so much you can do.

 

I get 19 at 75mph ahd 23 at 60mph in the 350.Skinny tires inflated to 65psi and a gearbox go a long way to getting those numbers.

 

I've thought about putting skinnier tires under mine for summer driving. The factory 265/75/R16 aren't fat by any means, but there are skinnier ones out there that are able to support the weight of the truck. The slush box part...I'm of the impression that once you get the TC to lock up at highway speeds, your not that far off from the gear-grinders efficiency ratio. Maybe I'm wrong there, but "light footing it" is the key; and the 5R110 will adjust it's shifting to suit the needs of the driver. Mine will shift into 6th at 50mph, and lock-up the TC at 60-ish.

 

^2 I agree with XB.

Watching instaneous MPG is very interesting on the scangauge2.
It's EASY to get poor fuel mileage, but it takes more patience to get
better fuel mileage. Be thankful with the PSD you get way better
than the v8/v10 w/o even trying.

 

Ever look at the specs of a E-350 with 6.0?
It has option for a 3.55 diff gear
A lot of Motorcycle race guys I run with have them and brag about 20mpg on the road all of the time....Oh yea van is Always packed with stuff....

 

x3 on agreeing with XB

Slow to 55-60mph when able and watch your mileage climb. I have a little lift and over sized tires and saw 18.6mpg when I was able to keep the speed down around 60ish. I did just start running Mobil 1 engine oil also...maybe that helped. Not sure yet.

Thad

 

Are these figures based on your imperial gallon?

 

Yes,I do a regular 900 mile trip each way about once a month and get a very good consistant avg of those numbers on summer fuel,winter fuel drops the mpg by about 1.5 but I tend to drive at 60 instead of 70+.

 

What's really interesting is displaying the tank average simultaneously with instant mileage. You'll find yourself trying to maximize the tank average, and then watch it just plummet with one short full throttle blast. It takes a lot of eco-weenie miles to make up for a half mile 7% grade at 40 MPH.