edwinsmith

My truck has about 160,000 miles on the clock. It gets about 19 mpg unloaded on the highway. Is that about average? It seems low to me. How can I get better mileage?

Edwin

crunchybuttr

You probably won't get much better than that, esp w/ the dually rear . Not so bad when you consider a gasser of the same size woul be averaging, what, 10? Search the site for economy and you'll find some tricks (Advance the timing, increase airflow, etc.)
Good luck.

G1625S

Sounds about right...pretty good for winter blend fuel. Airing your tires to the max allowable helps---specially since you have 6 tires to push around. You will sacrafice ride quality at 80psi, though. How fast do you run down the highway? I lost some MPG switching from the 18.5 to the 12cm when hitting the highway a lot. I run about 10 psi at 65. I got a little back by disconnecting the AFC line...I still have the boost, but no added fueling in reference to the boost. A valet switch is in my future. There will still be pumping losses at speed because of the tiny 12.
my .02

edwinsmith

I usually run 65 mph and I never accellerate sensibly. I agree about the gassers mileage though but my brother's 2003 V-8 GMC gets 22-25 mpg on gas.

My 92 S-10 Blazer 4.3L TBI gets 16 mpg though.

Edwin

gman07

I got 13.2 last tank with my W250 I would be delighted with 19.

stillsmokin

My w250 pulls 20 mpg now with 285 75 R16 very aggressive all terrains. But before I turned the screws and moded the turbo I pulled 25 mpg with 265 75 R16. Thats running 65-75 mph.

Boatnik

Glad I could help!

G1625S

Those 5.3's in the new chevys get great mileage! My buddy has an '04 and reports similar mileage. 65mph seems to be the breakoff point. I usually run just under 65 and hover between 18 and 22. Over 65 and pushing that horizontal corn-flake box through the wind gets expensive

Boatnik

I read alot of these posts and enjoy the time I spend on them. I have to wonder why we drive 7300 pound trucks and worry about mileage.

G1625S

Agreed. The mileage is just a bonus..now that I've had a taste, I'd drive a Cummins/Manual tranny truck no matter how much fuel it used

gman07

Lol yeah, if someone would remind me there aren't any mosquitos to fog this time of year it might improve some That was a tank with several smokings and no additive as well.

ihpower

i am not really worried about milage but last time i was able to check i was only getting about 13

Hemi Cat

Mine generally averages 17-18 running 75-80 with quite a few mountains. If I can slow down to 65 for a full tank and no smoking accelerations I can get around 20. I think it is incredible to drive a truck like this and get this kind of fuel economy!!!

KartRacer

I have been getting about 19 this winter since I blocked off my radiator. A 5.3 gasser will get decent mileage, but see what happens when you put something behind it.

-Steve

Boatnik

There are so many things that effect mileage. Gear ratios, transmissions, tire size and pressure and weight. Not only the weight of the truck but also the weight of the boot on the fun petal.