Nothing like smoke up the tail pipe!!!! 20+ and not lite on the go peddle!
Big thing about mileage is not just once getting 20 or just when you're coming East out of Denver, did 21+ myself with a 30ft goose neck, what do you get all the time.

 

Well, I guess I will go ahead and let the cat of the bag......44MPG while pulling a Semi Tractor Trailer through the Rockies @ 90+MPH. Tractor Trailer was running on flat tires (including myself) his truck was stuck in gear, Hurricane force 100+ MPH head wind, into a blizzard, and once I got REALLY going 100MPH I got 50MPG through WORSE conditons, Tornadoes, Earthquake, hail storm, 10 Foot snow drift on icy covereed roads. Can you beleive I got better fuel economy once I was unloaded???? Yep, 90MPG. Oh yeah, that was running on gasoline.

 

Well I am sure that I am getting better than anyone on here, but I have never checked it don't look at the overheard gauge and never ever plan on it. I don't care what I get it is what it is ya know. My dad is like that he checks his mileage like every 200 miles and bases his happiness on it, every trip it is like an emotional rollercoaster but I am sure you all aren't like that.

 

As long as I continue to get better than 12 mpg I'm stoked. My Titan only got 12 mpg on its best day. In comparison, I get on the Cummins pretty good. It's hard not to with the Quad box...

 

21.5 last night, hand calculated, only 2nd tank of fuel, 500-1000K miles.

I hope it stays there.....

 

That's how most people report their mileage on one exceptional occation. I also got 6.7mpg going to Denver with a 44ft trailer. What is the average of 21 and 6.7? 13.85mpg that's about right for loaded.
How about this lets see the miles driven and gallons used for 3 tanks. To be somewhat accurate you need to be putting in about 30gal. Yes I've done the old drive 100mi and fuel up and think I'm getting 21mpg. Doesn't take much error in fuel level to think you got 21mpg.

 

I suspect hitting 20mpg in a 1-ton crew-cab dually might be a little more difficult than getting it in a 3/4-ton crew-cab short bed. The guys with regular cab long beds probably do even better. The six-speed is more efficient than an auto. 50-60 psi in the tires is more efficient than 40-45 psi. These late model Cummins appear to be more touchy to various inputs than the older models. From Alvin through Pearland on Veterans onto Mykawa to Wayside to McCarty for several weeks I have averaged a minimum of 18.4 mpg on that route. On the highway 22 is not impossible at all. Even during the morning rush on 288 up to Spring Cypress I averaged 21-22 for two months on that route. No one else reading this post will understand but since you live in Pearland I thought you may get a sense of the type of driving for the mileage achieved.

 

Well all throw my reality in for the heck of it, and NO this does not put me in the 20+ crowd but I think is a good measure of what our trucks are capable of on average.
This trip was made in mid May from Centerville, UT to Flagstaff, AZ running empty w/ the exception of 100 gallons of fuel in the bed when I started the trip and 73.3 gallons less when I returned home. This trip was made without the juice (wasn't getting along at the time) and with EZ set on 2. Also for those who care the truck clicked 50,000 miles during this trip.

1324 miles total trip
25.7 HRS total trip
73.3 Gallons of fuel used

AVG speed of 51.51 mph
AVG mpg = 18.06

My .02 cents

 

Someone finally get's it!!!!!! We did not buy these trucks for the fuel economy, if you did, you bought it for the WRONG reason. These are pulling/hauling machines!!!!!!!

 

I couldn't agree more, these trucks are made to work and they do a great job at that. My last post was a fluck trip running empty but had to go look at a job in Leupp, AZ so I took the CTD over an airplane. It was one of my only trips empty so I thought I would throw it out there for all the grocrey getters.

 

if i keep my dually at or under 70 mph it will get 19.5-19.7 all day long empty....now keep in mind my truck is a very early 03 with the lightning fast 235 hp motor...which I can only imagine how the HO 305-310 motors feel like pullin...my truck pulls great and all stock....I think you guys with the higher hp trucks are averging less mpg's arent ya?
Cameron

 

...so I'm not that far off. I suspect if I did a full tank on the freeway I'd hit 20 MPG.

Yes, it's hand-calc'd. Yes, I fill up 30+ gallons every time. Yes, I take the time to fill it all the way up the neck every time (15-20 minutes ARRRRGGH). Yes, I'm not afraid to use the fuel pedal but don't do it at every traffic light.

And that other response is dead-on: We didn't buy these vehicles for their mileage. Mine replaced an aging Pathfinder that never got over 17 MPG in its whole (single owner) life, so I'm already ahead of the game and have 5X the hauling and 5X the towing capacity in the deal. I'm delighted!

 

wow thats awsome ! my identical truck with only 3 k miles is getting around 13 .so how fast were you running? flat ground? how many miles are on your truck? what modification have you done that made the biggest honest increase in mileage and how much did it give you? thanks

 

Well I think we all know there are TON of variables and there will always be variations, but hand calculation and filling the tank the same way every time is the best way outside of a laboratory. I mean I didn't just guess the mileage......

I was just surprised that the mileage showed such a high number with such a "tight" engine.

 

I completely agree but I'm not complaining, only reporting what "I" saw with mine.

I also bought my truck for work but I don't think anybody would pass up good fuel mileage.