Yes sir, I can't remember the codes, but if you do a search for REFLASH you should find them, there were two of them....

Good luck, and I hope that helps...

 

The computer is pretty accurate in that it can recompute your MPG constantly while driving under different conditions. It's a lot more consistent than my ability to put the same exact amount of fuel in the tank every time I buy diesel so I can pen-and-paper it.

I stopped using the pen-and-paper method after making my first long trip with the truck. I put over 5000 towing miles on it. When I was careful to fill up each time so there was fuel in the filler neck, my pen-and-paper averages came out pretty much the same as the computer.

Non-towing highway miles, keeping within the posted speed limits and driving sanely, I generally get close to 22 MPG.

 

yall are lucky.... maybe somthing is wrong w/ mine? although its running strong. my last tank i avg'd 10.4mpg, w/ 33's and stock gearing. plus i drive like a bat outta hell. but the truck is always empty, and i drive half on freeways (about 90mph @ 2000-2300rpm) and the other half is stop light to stop light.
im thinking about going w/ 35" tires, and going to 4.10's, exhaust/smarty in my future too...

 

I have just made a run from Myrtle Beach SC, to Louisville KY. This is 630 miles and includes some great mountain passes - scenery, and opportunity to blast a few good runs getting the boost up high. (no trailer, empty except for personal luggage)
21.4 mpg hand calculated, at 35 gl this would mean a total of 749 mls.
I need to do the tank vent mod, I know I can get more motion lotion in her.

 

I once got 26.7 MPG(imperial) hand calculated on a tank.
I was trying hard to see what I could get.
Secondary highway, never over 50 mph and reg highway, tried to keep her at 60 mph.
Was a chore to do and no fun.
Traffic was very light, but I would never attempt to do this on a regular day of traffic.
Can be done, but not very practical or safe.
But if you keep your foot out of it and try to keep your rpm at around 1750 to 1800 rpm you can get some pretty decent fuel economy...or you can just
trade 'er in on a Jetta.

 

Wow. I guess my stock truck with 17k miles on it is just jinxed fom the factory with a demon. It has never gotten over 17mpg no mattter how I drive it.Two different dealers say nothing is wrong wth it. Best I have gotten towing a 9000lb fiver rv at 70mph with the ac is 10mpg. You high mileage guys enjoy! I envy you!

 

Fuel mileage threads are like fishin' stories....

 

That's for sure!

We just got back from the DFW-ODRA event in Alvarado; after all of the warm-ups, burnouts and sled pulls (4 runs), overhead reads 21.5mpg... must be true, eh?

 

Oh yeah, I just left Albuquerque for a road trip back east yesterday. My DTC was reading a very nice 22.8, doing 80mph in NM and 75 in Texas on Level 3. I knew it was too good to be true. I stopped to fill up, after 523 miles, I only got 17.1 hand calculated. The DTC was just a tad off.

 

Not trying to flame, but I am curious, for my own knowledge....How did you calculate mileage with the 35s on? That will throw the odo. off and I was under the impression Dodge dealers can't reflash for a 35" tire on our trucks...

 

Just put little over 300 miles this weekend on my '06, its an auto and thinkin 3.73 gears, and 18.4mpg is what i calculated at 75mph mostly. Just changed the fuel and air filter, so thinkin this is her best. Love her to death though, drove a jeep before this, got the same fuel mileage but had less than 1/2 the torque. Cummins rocks.

 

To get great fuel mileage you will need to slow down and drive between 55-62 MPH and most people will not drive that speed to get the good mileage from there truck. When mine truck had under 1500 miles I took it on a 3800 mile trip from IA to OR and back along with a side trip in to Yellowstone Park driving at a top speed of 72 MPH and got 18.35 mpg for the whole trip with about 1100 Lbs of stuff in the truck.

BTW I've gotten my best mileage from my 2006 (21.5 mpg empty) while driving between 55-60 MPH (using 12 oz of Lucas in the fuel) and I've gotten 18.55 MPG (using 16 oz of Lucas in the fuel) with 2,000 lbs in the bed while driving on state roads at 55 MPH. Once I drive over 63 MPH I know my mileage will start to go down so I try to drive as much as I can on state or county roads being the speed limit is 55 MPH.

 

second that X2

 

Fuel mileage is purely a function of load. You can consider the mileage to be a weighted average of the engine's efficiency over a period of time.

For instance, here are some snapshots of fuel efficiency for given scenarios:

1. WOT from a dead stop: 3-4 MPG
2. Highway cruising @ 50 MPH: 21 MPG
3. Highway cruising @ 75 MPH: 18 MPG
4. WOT from a roll: 7-8 MPG

Let's say you drive for 1 hour and your time at each of those loads looks like this:

2 minutes of #1
45 minutes of #2
3 minutes of #3
10 minutes of #4

That would be:

(3.33% * 3.5 MPG) + (75% * 21 MPG) + (5% * 18 MPG) + (16.67% * 7.5 MPG) = 18 MPG

Your MPG is completely dependent on load and time spent under that load, which depends in a large part on truck steup, throttle position, and driving conditions.

When I get bad fuel mileage, I always blame my county road planners or my right foot, not the truck.

You guys getting 13 MPG, try this: find a long country road with a speed limit of 50 MPH. Get up to speed at 50 MPH, set the cruise, and reset your overhead. If you don't get 20+ MPG, THEN you know something's wrong with your truck. Otherwise, just chalk it up to your driving conditions or driving habits.