Fuel Mileage Experiment

[AHarris]

With some careful driving the last few days, I've been able to increase the indicated average fuel mileage to 17. 2 in city driving and 20. 5 highway.

For the highway piece, I accelerated gently and set the cruise at 65 on a 40 mile stretch of Interstate 20 East of Shreveport, LA with a light headwind, mild rolling hills, and about 55 degree temps. Reset the indicator at the beginning and mileage creeped up to about 20. 5 and stayed there.

For the city piece, I pretended like I had an eggshell under the go pedal. Coasted up to lights and didn't stop unless I had to, trying to retain as much momentum as possible. On longer stretches, I feathered the throttle just enough to maintain the speed limit and allowed the transmission to stay in the highest gear possible keeping the RPMs around 1100 most of the time.

Normal driving gets me 12-13 in town and 16-17 on the highway running 77-80. It's nice to know this big beast is capable of respectable fuel mileage if I use a real gentle right foot.

 

[MChrist]

If you look up "hypermiling" online, you will see that what you are describing is what they do there. True, everything you do to increase efficiency helps. I look at it as a math equation: using brakes hard uses up the energy spent to get to the speed you were at. So why not coast. Also, I found that a accelerating down hill, then slowly backing off while going uphill saves fuel, too. All little things that do make a difference.

One of the diesel mags had an article on mods to get a 12 valve dually up to around 30 mpg! Wasn't very practical, but shows how you can use physics to help with mpg.

 

[mroodzant]

Wait till you break your truck in. The faster you drive the better fuel economy you will get. When my 97 hit 100k I started noticing this trend. Now I am seeing the same trend with the 03

 

[Gunny]

I got the best miles ever in my old 2001 HO 6 speed, 4x4 of around 17 Hiway around town for me was never really good.



The newer 6. 7, 6 speed, 4x4 has always gotten dismal milage. Pulling my enclosed trailer, hauling a hot rod weight around 10,000 for trailer and load, Monday from Alabama to louisville, Ky I also played with the milage thing. Cruise set on 70 and got 10. 2 MPG, cruise on 65 got 12. 8, cruise on 60 got 13. 5 and with cruise on 55 got 15. 9 MPG. In the end I have to face facts I am never going to drive at 55 MPH unless I have to in construction zones etc. Milage in this 6. 7 is going to be what it is and thats not good. It will however hual just about anything I can put behind it and thats why I have the rascal.



RS

 

[Beast2B]

I know what you mean, Gunny. I got 22 mpg on a freeway run in my 2001 HO within the first month of owning it. I went all the way down to 17-ish commuting after getting to 435hp, 4. 5" lift and 37" tires!

My 2010 bone stock stays around 14-15 with 6800 miles on the odo