I'd also be VERY amazed if losing the cat and muffler is worth 2MPG.

But I would like someone to tell me how much for real!

 

I've got an 03 dually, 6 speed. 24.9 MPG yesterday at 55mph. Anything over58 it will fall drastically. Now only if would run right?

 

I got my overhead to 25.0 today, which means maybe 20.x when I fill it. I will probably top off in the AM. At least 360 miles are gone by on this tank.

Again 1900 is the MAX rpm I'll ever turn in cruise. Every once in a while I foot it.

 

I have a 03 RAM, Quad cab, 4.10 axle, 4x4, HO Cummins, 12000 GVWR, LB, SLT, Auto tran, 25800 miles, and I am getting 11.7 MPG as listed on the mileage guage, and when figured on number of gal, into mileage...I am pulling a truck camper weighing 4800 lbs. I do not know if that is good or poor....but I have not seen anything like 15 mpg even without camper....Maybe when its broke in....oh well .....

 

What I posted is what the overhead gives me,no lift or anything on it,265 tires.

Pav

 

Yeah, I have got my overhead to read 99 MPG before at 70 MPH

 

Crud! It would have been bad enough to have had to pull the 5,400LB tank trailer to the customer and back. But I had to drag it about three times as far empty. With odo at 500ish, MTE was down to 170ish.

I guess it could be worse. I could have a gasser.

 

Huh! I got 682.x miles and put in 34.xxx gallons (hard info is out in the truck) but even with the trailer when it was all said and done this tank comes in right around 20MPG.

Man I LOVE this '03!!!

 

When I made the decision to go for a diesel, best fuel economy was paramount.

I searched for one last spring ('03 or '04) in two-wheel drive, longbed with the NV-5600. Found a cherry unit on dealer trade-in lot with Leer topper and 120,000 miles. I always drive for economy and see:

17-19 mpg in town
21-23 mpg hwy (66-68 mph)
13 mpg towing on back roads
16 mpg towing on Interstate (62-63 mph)

(The towing mileage is lower than it should be. I have an enormous gap between truck and trailer and will be working towards "helping" this problem; expect 16 mpg at some point).

I replaced the original tires (see odo mileage above) with the same (Michelin LTX A/S oem size [a very good tire tread for mpg and long life]; set at factory recommended 50 psi all around) and added Bilstein shocks.

Am planning a run to Laredo and back soon, at about 58 mph to see if it will break 25 mpg (after valve lash maintenance scheduled).

(Yes, all figures are derived from records).

I also use FUEL POWER FP-60 (in five vehicles the past five years; sometimes mpg increase, sometimes not) (Also have been using Startron Enzyme Treat from West Marine). Other change from stock are AMSOIL oil and air filters. Shell Rotella 15W-40 with Amsoil/Donaldson oil filter and LUBE CONTROL LC-20 (first oil analysis to come shortly). All fluids changed with MOPAR fluids. Alignment perfected.

In the extensive reading I did in the years prior to purchase I was always on the look out for economy, and two things came up consistently on newer trucks:

1] 2003-04 had the best fuel economy, probably;
2] The CTD is more sensitive to aero drag than to weight (an aero 9,000-lb trailer is better on mpg than a 5,000-lb tall box; fifth wheel sometimes better than conventional trailer; etc.).

Learning to drive big trucks ten years ago broke me of some habits I'd acquired, habits that persisted even though I had always driven for economy since first learning to drive 35-years ago. It is no big deal to be the slowest vehicle out there (and it is prudent as these trucks handle like pigs and are hard to stop), it is only a mind set.

I made up my mind to learn (to truly stick to) "progressive shifting" in those Freightshakers, and it comes in handy now. I take it out of First at 1600, Second at 1700 and Third at 1800, then use 1800 or 1900 for Fourth or Fifth (unless towing or ?). I'll add some gauges at some point and learn to use them on this truck.

The difference between this truck and those big tractors isn't as noticeable for shifting, BUT it keeps me focused. Disciplined. I want the least amount of throttle opening to get to speed (all trans, not motor) AND I don't ever want to use the brake, so I downshift usually. I always try to keep the motor between 1600 and 1900 regardless of road speed. Downshifting, I match engine and road speed.

If you follow me in city traffic, then you'll rarely come to a full stop as I back out of it a long ways off from the light. A standing start is what kills city mileage.

For the highway I stay a little under the limit (again, prudent safety) and observe any speed-regulated curves or ramps.

And try to drive in such a manner that no road or weather condition would alert a light-sleeping passenger that anything was amiss.

I could probably go with a higher rear gear ratio, but the only difference would be that I might be able to better match gear and posted speeds. The gearing/tire size makes for easy hill-climbing empty or loaded.
(But it would be nice to split the gears . . . .)

I figure that not only will fuel prices continue to increase, but that shortages will become common. And, of course, we have troops dying in the Middle East over this stuff. Prudence dictates I learn to maximize fuel mileage to be able to predict how far I can go under varying conditions. As it currently stands my 36-gal fuel tank will take me about 700 miles at 65 mph with a comfortable reserve, solo. 450-miles towing.

150 miles in an all-day stop and go hurricane evacuation (with trailer). The reading I've done, and stories collected indicate 3-5 mpg for about any vehicle in that lousy situation. Have to get a few 5-gal containers and a rack before May 1st.

 

19-22 All The Time At 65-69 Mph. The Lower Rpm Help. Mostly, Its The Way I Drive The Truck.

 

Stock tires no leveling kit and an Edge Juice set on #1 with an Amsoil Nano filter gets me 21 MPG avg on the hwy with the cruise set at 70 MPH. Set cruise at 75+ and it plummets down to 19.5 Ish. Town is a consistant 14 MPG.

 

I hate all of you...
I get 12-13.5 MPG in my rig..

 

I'm with you! I just bought a very clean 2004.5 3500 4x4 auto dually 3.73 ratio, 39000 miles, it is bone stock, stock tires. Empty, highway, 12.9 mpg babying it at 67 mph no matter what. Clean air filter, clean fuel filter, fresh oil and filter.

 

Did you get your speedo recalibrated for the larger tires? That will affect what you think your mileage is... Larger tires = lower calculated fuel mileage.

 

If it ever comes that to get what I want means 4x4 I will sell my soul to get manual hubs!

I have a several hundred mile overhead average going and picked up .2 by getting stuck at 55ish for 30 odd miles.

My overall average is holding at 19.2xxx (.23 or 24 mostly).

I'm thinking about SOMETHING to smooth the airflow around the flat front of my tank trailer!!!