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Mileage

3K views 10 replies 9 participants last post by  your nightmare 
#1 ·
Alright guys need some help you see what i have in my sig but for some strange reason i still can barely manage to get 16mpg even driving easy even in town i get that but once i get on the highway it goes south and im driving like 60-65 mph going across nebraska on a 500mile trip. Seriously i got that with the truck in stock form i went up to a 285-65-18 tire i know you can lose some mileage due to tires/wheels but this driving me nuts i know i helped my reliability/performance of my truck but mileage didnt do jack sh**. Any ideas of what i might try besides going back to stock size tires and taking that da** leveling kit off cause it rides like sh** now. Sorry for having a few choice words but i just had to vent.:bang: Thanks
 
#3 ·
I agree with the winter diesel. Even here in TN where it doesnt even get close to being cold enough for it is still sold. my truck is stock and I do good to pull 15.5 during mixed driving conditions. I know the cold weather will also put the big suck when you are talking about fuel economy.
 
#4 ·
Don't feel to bad. I just drove 850 miles pulling a very low unloaded bumper pull trailer and got a whopping 12.5 MPG AVG. I filled up before I left and again about 1/2 way home and one more time (about 20 gallons) just before I got home. That was a non-stop drive, point to point took just over 10 hours. I 'think' I've hit 15 once but never on 3/4 or more of a tank.
 
#5 ·
Stock or any mods on your truck?
 
#7 ·
I saw some increase in mileage whene I installed the dioblo sport power puck. right now with the power puck and bully dog I can get 21 mpg easy on the highway
 
#8 ·
First I don`t how cold it is down in Wyoming at this time of the year but the main reason for poor mpg is cold weather and winter fuel. See I get around 22mpg 2/3 of the year but at this time (you don`t want to see how cold it is uphere) I don`t get anymore than 18 to 19 mpg so wait for warmer weather. Same for all the tractor trailer at work; we get around 8 mpg with warmer weather and no more than 6.5 mpg at this time of the year. Cold weather is the diesel engine worst enemy when it comes to MPG and cold weather also means winterize fuel. :happymugs
 
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#9 ·
Thanks cocotte it was just starting to get me to kinda worried put couple thousand worth of aftermarket goodies on and drive it easy for the most part and got darn near 50,000 thousand on the truck and no better mpg. But ill wait till summer till it warms up thanks again guys
 
#10 ·
Some Towing Fuel Economy Figures.........

All truck info is in signature; I had the ECM updated to reflect my "old" LT285/70R17 Firestone Destination A/T's. I now run some 20x9 Ultra Grinders wrapped in some LT305/60R20 Wrangler SR/A's. I now have to multiply my odometer readings by 1.0683 to compensate for the 20's.

Anyhow, my truck now runs 1,750 rpm at 75 mph, as verified by my Garmin.

I contract haul some on the side; this past Friday I hauled a 1988 Airstream Excella triple axle travel trailer (34 ft and around 6900 lbs) from Hebron, OH to Berea, KY. I left out with a full tank (only had 17 miles driven out of it) and went 278.3 miles and averaged 17.652 mpg with an average mph of 61.84(Juice w/Attitude on #1). Within 10 miles of my destination, I re-fueled and then hooked up. I drove 288.9 miles and averaged 12.862 mpg with an average mph of 56.64 (much lower mph due to an accident delay) Juice w/Attitude on #2. I also have the H&S DPF Delete, too.

That ol' Airstream tri-axle pulled like a dream......I had a standard solid ball mount with 6" drop (no weight distribution hitch) and no swaying and tracked as good as a new one, I'm sure. I was actually apprehensive of the weight and the fact it was a Class IV style hitch. The 6.7L and 68RFE and 3.73 gears are a great combination IMO.

Greg




 
#11 ·
i used to get 20.5 running 75-80 with all my mods dealer gave me new flash update :bang that lowered it to 19 now with 37x14.5 tires I run 1450 rpm at 70 and get 18 :bang thinking of going to lower gears have 3.73 now
 
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