Hate to keep asking about my fuel mileage.....

[Dixie Dawg]

but I've yet to break 15. 5 mpg thru 2500 miles. Most tanks have been right at 15, the last was 14. 9. All manual calculations. All city driving, most short drives, no towing. About twice a week, I take it up the interstate with O/D off, about 3 miles @ 2400 rpms, just to get her warmed up because I only do city driving. I have 3. 54's, and usually run without O/D. Should I consider a computer flash? This is about 20% less mpg than I was expecting, albeit after break in. Anyway, Thanks for any and all help!

 

[CumminsAholic]

3 things I can see for sure. 1. Short trips, they're hard on mileage. You'd see way better mileage if you went on a 3 hour trip. 2. Your miles. In time, when the motor breaks in you'll probably gain 2 mpg. 3. Running without OD. Especially on a short trip. Yes it's good to warm it up, but also hard on mileage. When you add all 3 of these things together they add up. Go on a longer trip sometime (say 150 to 200 miles without stopping) and calculate the mileage, I bet it's better.

 

[tgbol]

I wish I could get 15 around town. I get 13. 8 consistantly. 23000 miles in 11 months. I think it could have something with my size 14 boot. When I baby the pedal I can get it up to around 16.

 

[pwr2tow]

Dixie Dawg,

If your getting 15 MPG and all city driveing I would say that is about right to fairly good. I get 16-17 MPG combined city and highway, about average, some get higher some a little lower. If you want to make yourself feel better take that truck out on a highway cruise for a couple hundred miles at 65 MPH, fill up before you leave then fill up when you return (at the same pump) you will be amased. Also pull something to help seat those rings and that will also help mileage. rent something to pull if you have to.

Ron

 

[chuck3]

MPG's

Dixie, Ron's right, I get 15 to 17 mixed driveing, but on a long trip at about 70 mph I can get 20 to 21 mpg, Try it.

 

[JJMiller]

Do you have the trip computer? If you do, try this (if you don't, read on anyway, I'll tell you what I've observed).



Go to a "gas" station close to an interstate or major highway. Fill up, and reset the Trip Computer (reset everything, especially the Average MPGs).



Set the Trip Comp so that you're looking at Average MPGs



Start driving with an easy foot and get on the highway. You'll see the average mpg's tick up as you go. Eventually they'll start to level off (the effect of your idling and pulling away from the gas station becomes less significant as you put the miles on).



Romp the throttle. You will see the average drop quickly. One good WOT up a little hill can knock a 22. 1 down to a 16. 7 in a hurry. Let off again and drive normally. You will now see how much driving it takes to get back up to the average mileage you had before you got on the pedal.



Now go home through town. Watch the average drop every time you sit at a stoplight, start from one, accelerate after granny makes her 5mph right turn in front of you. You get the point.



Your truck does get great mileage. Probably somewehre on the order of 17-19 for a new, non-broken in truck. You just never see the great mileage because you put those city miles on.



Just think, though. You could be getting 8. 5 to the gallon on a gasser, and not having 1/2 the fun, AND be paying more for fuel!



--J

 

[Sarge]

Milage

I dont know what you used to drive, but here is something to think about. If your same truck had a gas motor in it, you would be lucky to be getting 7-8 mpg. With the 4X4 drive train that you are running, even if you could disengage the front drive wheels completely, you still are looking at approximately 30% more rolling friction from your 4X4 over a 23 wheel drive truck. And considering that physics says that 80 to 90% percent of the energy created by your burning fuel is used to overcome the friction of moving the air in front of your vehicle. Not that any of this may make you feel a whole lot better, but considering what your diesel is up against, you are doing pretty good! But take heed, your engine will loosen up the more miles you roll up, and your milage will improve. If you can, tow a trailer for someone on 200-300 mile trip. It will help you loosten up monster all the faster

 

[Big_Daddy_T]

not so bad

Yeah city driving in a bustling city really knocks the tar out of mileage. I think you overestimate its capabilities. I get 14 to 15 when driving in town with my lead laden appendage. Although ive seen as high as 26 towing 2 snowmachines 400 miles. I read once that it takes 400 percent more fuel to get from 0 to 60 than from 10 to 60. Have you ever seen the truckers rolling up slow on a stop light they are trying to preserve that precious momentum, think about it when you fly up to that next red light.

It takes a big pusher about 3 times more energy to go 60 than to do 45. Wind is a major factor but in a city your not able to do warp factor 9 too much. The best advice you can get is dont hot rod it. Drive conservative and I bet it improves. Alot of people have seen some improvement with fueling boxes. I am not one of the lucky few. Good luck

 

[BarryG]

I also was beginning to feel that my truck was not performing anywhere near my mpg expectations especially after I hit the 15k mark. So I did some experimenting with my driving style. On the freeway I am not above driving 80 to 85 on the open road and was only getting 17 mpg unloaded. Last trip I took (approx 500 miles) I took it easy and stayed between 65 and 70 mileage went up to 21mpg on the same trip I have taken many times with only 17mpg. That trip from Denver to central Utah is over several high mountain passes and sustained long uphill grades. In town, I am moving and now have a new commute. Before It was all city stop and go now it is a mix of highway and city. Mpg has gone up approx 2+ mpg with a relatively easy right foot. Went from 151/2mpg to around 18mpg. Much happier now as it is what I was expecting. Just needed to lose some weight in my right foot and drive with a little more attention on the mileage aspect.

 

[superdave]

i have 1999 3500 auto , stock, that was getting 19,8 at 75 to 80 mph with 8000 miles on it... pulling heavy loads, fifth wheel and gooseneck flatbeds got 16. 8..... these were consistent from about 5000 to 10000 miles... both from computer as well as manual figuring. . went in for minor warranty and the dealer flashed my computer. . supposed to improve power... wow did it screw up my fual usage... went down to 15 empty and 11. 6 to 12. 4 loaded... all driving in relatively flat East Texas,,,cant pass a fuel station anymore... . hate this... . DC says sorry, they can not do anything about it... also now i have 40000 miles on it and since the flash i have to maintain at least 2100 RPM to be able to maintain freeway speeds with even a small 16 ft, trailer empty behind me... love my truck but hate my mileage... if i DID have a power improvement it would not be so irritating but the power never changed from day one... thinking about a Banks system to attempt to improve mileage as well as power in the mid range RPM,,,ie: 1600 to 1900... . dont let the dealer flash your computer unless you have a newer truck,,,,goood luck..... i am looking at a duramax now... . also have a 2000 ford PS diesel with 13000 miles... has gotten 17. 4 since day one... also has a nice large fuel tank... .

 

[redneckdr]

mileage

dawg. :

i have essentially the same truck you have. i get about 15 under the conditions you relate, but around 20 on the interstate at about 70mph. this is thru 7. 5k now. actually i was thinking it was pretty good for the truck. i just traded out of a '98 dakota ext cab 4x4 with the 318, and was getting about 14 on a good day. i'm satisfied. your mileage will go up as you get more miles on it... ... . hang in there.

herb

 

[RustyTRanch]

I just made a trip(running empty) and ran 70 mph into the wind and drove 551. 8 miles when the silly warning light went off and fuel up with 26. 106 gallons(21. 14mpg)



return trip 553. 6 miles /26. 566/20. 84 no wind,but ran 75mph



I am happy with my results

 

[KMeek]

I understand your concern. I have the same fear with my new truck that has less than a thousand miles on it. My first partial tank was after a 100 mile drive at 75 and only yielded 14. 75 mpg (hand calculated). Next partial tank was mostly in town and I got 17. 25 mpg. Then last weekend I took it on an extended trip that ended up using a full tank with 50/50 city/highway miles and got 17. 75 mpg.



Watching the computer I see that my best mileage right now is at @ 63 MPH. I do not get very good mileage at 70 and up like others have stated. Having previously owned a Dodge V-10 I have a tremendous appreciation for the mileage I am getting so far.

 

[Floor It]

I've gotton bad mileage from day one! 15mpg in town, nothing compared to my 96 12v truck. I know its emissions, but in my opinion this new 24v sucks.

 

[MCummings]

LOL Floor it.

Might there be a TINY Reason the MPG is low??

How "Doubtfull" are you hehehe.



My peak MPG has been 25MPG Traveling a very steady 60-65MPH (But had a peak of 80MPH once was going downhill)

My peak low MPG is 9MPG, that was with Boost, and Exhaust Leaks.

After clamping tight all Exhaust and Boost hoses. I instantly went up to 12MPG.

All my MPG measurements were with a straight pipe, and a Stock motor, that had been reflashed.



I got about 12-16MPG before BOMBs, I haven't checked Mileage with my "BOMBs" but I expect it to be,, uh,, "low" I've got a Plutoniom foot, and I drive stop and go traffic, and that Smoke is just, wayyyy to fun.



MerrickNJr



P. S My previous truck, a 2000 (new body style, not HD) 2500 2wd Long bed Ext. cab, got about 12MPG Daily (peak was 17MPG WHOOHOO), and could easily go into the 6-7MPG range if I drove it like I drive my truck now.

For one 250mile tank (not towing) I got 7. 2 MPG. I only towed for about 50 miles of the 14K I had on the truck.

 

[redneckdr]

mileage

hey guys--we're not talkin' vws or honda civics, here. these are 6500-8000 lb 4wd trucks, in many instances. you want bad mileage, talk to the guys with similar trucks but V10s or big V8s i used to think 8-10 mpg on my old w350 4wd dodge wasn't bad. i, for one, am amazed that i can get 20+ mpg with this truck. heck, i get about 12 mpg with th' rollin' redneck residence and it weighs in at about 25,000 lb. i grin from ear to ear about both... ..... my two lincoln's worth... ... .....

 

[jtisdale]

I get between 14 and 16 in the city. My last trip to Chicago, I got 19. 625. This is a 24V 6er 4x4 3. 54 QC with 4300 miles on. I can't wait till I get another 20K on it. And she is definetly NOT short of power. My last (95 reg cab 5 speed 3. 54) did about 21 at best, and what a dog compared to this power plant.

 

[KatDiesel]

Might latest figures is 14. 5mpg. I added 4% for my 285/75/16 tires. With all the intown driving I do I consider that pretty decent considering the way I drive. Many people can attest that I drive it pretty fast... ..... Floor It would be one of those people Since adding the COMP it is never off, typically stays in Level II. Only crank it upto Level 4 or 5 if I see a potential "situation" but so far no one will really race me it seems, now its even garder with the new hood.

 

[GBerry]

I have to second what SuperDave said !!!! my 01 auto qc 4x4 265/75/16s was getting 17. 8 to 18. 6 or 7 new went in to the dealer and had them rebalance the tires and they reflashed the ecm lost a solid 2+ mpg and dont think it has the same power it had !!! now I get 15. 8 to 16. 1 consistently thats 26mi back and forth to work mostly highway and country road for a total 52+ mi per day have 30,400miles on the truck now, granted the highway around here is not flat much of anywhere!!





Dixie Dawg..... I think what most are saying is about right good mpg for city driving and Im sure your highway mpg will be much better and the more miles it will get even better !!!



still love my truck just hate DC monkeying with the mighty cummins turbo diesel!!!!

good luck Dixie Dawg!!

Guy

 

[tgbol]

My Average Mileage around town is 13. 8. Sometimes when I get out of school late and the gauge is low. I play a little game. I set the computer to distance to empty. Then I will set the cruise control at 55 and see how miles add up on the computer. The other night the computer said 54 miles, 37 miles later the computer said I still had 48 miles to empty. This truck must make fuel at 55mph