Well. I'll tell the truth on mine, so far it sucks. 12.5 towing appox 5000lbs with mine so far. I need to get it further broke in.
My co worker says his started out at 12-13 but after 2500 miles it has worked it's way to 15.6 combined towing and unloaded on his last tank. He pulls a 31' travel trailer.

One thing mine does have is lots of power. After my last Chevy fiasco, I drove ALL the Dodge Trucks I was interested in and picked the one that ran the smoothest and had the most power.

I don't mind buying a power adder or any other accessory that will help. I don't want to spend 5-600 bucks and get worse mileage. One thing I don't really need is more power.

I do have a drone at about 66-69mph when towing from the exhaust that I need to address.

 

My mileage is almost identical, I've been getting 13.5 city/17.5 highway. That's running empty. Highway mileage was running at 65 mph. I've also got about 1500 miles on the truck.

BTW I've got the six speed manual trans. As high as the rpms run on the highway, I wouldn't get the 4:10 gears even if they were available on the manual trans.

 

I pulled my 26 ft extra tall enclosed for the first time this weekend 1800miles on the truck now. The trailer with contents weighed in at 6500lbs. I pulled at 75 to 80 MPH for 200 miles and got 12mpg even.

For pulling a brick wall that fast fast with a truck that's not broke in that's pretty dang good IMO.

On the free Way at 75 to 80 I'm getting a hand calc of 18.5 so far.

 

mine has been 18 +/- a few tenths, handcalc'ed, unloaded for most of the winter. I did throw a 8-9k load on it right after I passed 500 miles, and it kicked my mpg up about 1.5, since I was getting ~16 those first 500.
Most of my driving is 40-45 mph though, with not a lot of stop and go...
That first load I got around 15mpg on county highways, ~55mph.

 

depends how fast i drive, but with crazzy lary and quad my wife gets 20-21 handcalculated driving 65mph. iv got too heavy of a foot exspecialy when i go under a bridge.

 

This tank is going to be even higher than that. This is with ~2500 miles on the rig. Once warmer weather arrives, and they stop selling winterized diesel, I expect to break 20 MPG in mixed driving. Highway should be above that.

These are honest numbers. I've tracked MPG and hand-calc'd since the very first tank. It started around 14.x, went to 16.25 on the second tankful, and has gently increased with every tankful since. I'm absolutely thrilled, even more so because it's already beating the MPG of the vehicle it replaced (a 1993 Nissan Pathfinder) which weighed half as much and had only 20% of the cargo and towing capacity. It never exceeded 17 MPG (mixed) and now I'm driving a REAL truck and getting better mileage.

BTW, one of the things that tipped me over into buying this year (2006) instead of waiting is that next year's diesel engines are going to have even more EPA-mandated garbage on them. I seriously doubt even MORE EPA hardware is going to improve mileage.

 

my truck is sucking down the fuel I get 12.1 empty and 10.3 towing 8,000 lb trailer 2100 miles on the clock

 

Something's broken - get it looked at. There's no excuse for numbers that low.

 

I took it to the dealer yesterday and they told me I should drive it more before I check the mileage. We will see what happens.

 

Power means fuel consumption when the truck is in stock form.Dont get me wrong all that epa bull!#@! doesnt help but if you take the old 12 valves my 95 on a bad day gets 20 MPG and all it that is done to it is strait piped.My 05 on its very best day if the RPMs dont go over 1800 sees 17 mpg.But there is a night and day difference between the two on power.

 

I don't know what the differences are between my 04.5 and the 06 DC. Like nearly all others, my fuel economy steadily improved as I added miles. Now at 21K I am pleased with my mileage. I completed a 2500 mile trip to from WY to AZ and back and averaged 20.4 hand calculated (19.9 overhead)
Keeping rpm's at 2000 and under will help, as will many fuel additives. I use Stanadyne.

 

Allright Here we go
Truck mileage between 839 miles and 1244 miles
405.5 miles total on 24.899 gals = 16.28MPG Most of this tank probably 300 miles of it was in highway (city Highway) driving with 100 miles of freeflowing city traffic. All unloaded, freeway speeds 70mph.

Oh yea, overhead console said 15.6 MPG.

 

i just got my rig monday, i had to scale back from one with a sunroof, 3.75, and some other upgrades because of price and ended up with a very similar one with a 4.10. i was pretty nervous the morning after because of the potential increase in fuel consumption. i have several ways to get to work, 35 miles one way: mild hills but almost flat, a couple of bigger hills with a lot of flat, and up and down the whole way. The latter 2 are the most fun. im only using the computer right now but, i got about 15 on the slab route, 17.5 on the middle one and i wont even mention the other one cuz i was tearing that one up(about 13). im theorizing(hoping) the 4.10 mpg impact mainly afftect top speeds? this is such a small sample though on a brand new ride i would expect(hope) i could get these up some with better driving. i'll probably put 285's on when the current tires are done to see what that does. also it appears there is mixed opinion on mileage increase due to breakin, whats the logic behind this alleged increase. lrdchaos whats your axle ratio? im not too worried though i make some high grade biodiesel and after the first 2 or 3 tanks of petrodiesel im at b20 at least.