Here's my experience with my 06 dodge 5.9 TD:
First, a few facts
- 06 dodge ram 2500 quad cab automatic trani with 3.73's
- upsize tires from stock 265's to 285's running an all terrain tire.
- topper on the bed, open-faced air filter and box, amsoil full synthetic in ft and rr axle and transfer case, and quadzilla xzillaraider 2 power module
- Winter blend diesel hit the market sometime early November after the temps dropped below 30* at night consistently.
- 34 Gallon tank with fill up's being consistant (level, to the cap, blah blah blah)
- Never ever ever ever ever rely on that overhead for mpg reading, only thing that's good for is direction your driving.
I have an application on my cell called mileage monitor that helps me to track my mileage over time and here is the output from Sept 30th '09 to March 9th, '10: (NOTE: if i don't fill the tank to the top, it doesn't give me a mpg rating until the next time I do.)
3/9/10 (15.3) (Pulled the TT 65 miles round trip to a local campground, the entrance has a very steep grade 7-9%(?) and we climbed it twice. Rest of tank was to work and back, 100 mile r.t.)
2/23/10 (18.8) (work and back, 100 mile round trip, pt hwy pt city 5 days a week)
2/15/10 (17.8) "
2/2/10 (17.2) "
1/2/10 (17.8) " (Partial fills in December, so no data til now)
11/16/09 (17.5) "
11/7/09 (17.2) Winter blend diesel started somewhere in here
10/28/09 (19.3) Still summer diesel
10/16/09 (14.2) Pulled the TT 330 miles from Pagosa Springs to Greeley (via hwy 285 on the north/south) there's 3-4 passes along that way with avg speed somewhere around 65-70 in the flats. 7.5-8 hour trip.
10/4/09 (19.3) Drove to Greeley from Pagosa Spgs same@70-80 6.5hrs, empty
9/30/09 (19.6) Drove to Pagosa Spgs from Greeley same@70-80 6.5hrs, empty
With that said, the very best mpg i've ever made in a Dodge TD was in my 04.5 model, 6 speed stick, 3.73's turning 285's AT's again with an average speed around 60-65 mph empty was a trip from Durango to Greeley via Pagosa Spgs (trip consisted of travels between Bayfield, Durango, Mancos, Cortez, and then thru Pagosa back home and then to work and back a couple of times). On that trip, it turned 21.8 mpg (700 miles on a 32 gallon tank) and had enough to get back to the station on the way home. I have pics of the odometer, fuel gauge, and overhead mileage & hours because I couldn't believe it myself. But figure, on average, I was getting 16-18mpg consistently, no matter if i was traveling the interstates or driving to and from work. The mileage is always effected directly by your speed, 55mph with stock tires and empty would probably produce some nice results, but where in the heck would I be able to do that?