I have an 05 2500 4x4 w/ 2200 miles thats getting a hand calculated 12.7 mpg in the city. I am very lightfooted and am currently at sea level. This seems rather high even for its low miles though maybe I am wrong. Any insight would be greatly appreciated.

 

When you get 10000 mile on it mpg will get better

 

Mine got significantly better by 5000miles

 

the more light footed you are the longer it will take to break in.

 

I am getting anywhere from 16 to 18 around town with 5000 miles on it now. I also use the ps/mmo mix.

 

Try the tone ring or ROKK sensor mod. Seems to help the 6X0 motors. A good additive like PS/MMO or Lucas helps too.

 

I ordered the Rokk Tech sensor the other day hope it will make a difference. I also am considering purchasing a programmer. It all adds up. I do 50,000 miles a year so even a combined gain of 3 mpg would make a decent difference. I also eagerly await the end of break in. THanks guys

 

Tell us about your truck... axle, transmission, tires, 4x4, your driving habits.

I don't mean to brag, but I can get 20 MPG in the city driving fast but gentle. I get a lot of 40-50 MPH cruising on secondary roads in the city and that is probably optimal for MPGs.

I can't think of anything truckish less expensive to drive other than a 4 cylinder mini truck and even then not by much.

I noticed my engine was very tight when I got it. I pulled our 9500 pound 5er about 1500 miles this summer, through a lot of mountains. I made the engine work hard. I sometimes wonder how I would have gotten the engine to break in if I didn't have my trailer.

 

I get a constant 16.4 mpg around town/highway.
27k miles.

 

The local diesel guru wants to put a Triple dog programmer on it. I did a more indepth search and found alot of folks complaining about similar gas mileage. I should have searched before I'm sure you guys get tired of hearing it.

 

Bud,

Believe it or not, you are doing yourself and your CTD a big disservice by babying it. I have built engines for a living....both street and race, and I had a hard time believing it was true, but Cummins NEED to have a load on them to seat in the rings, or you will end up damaging rings and pistons. Keep in mind that your engine is not getting that high in the revs (understatement), and that these workhorses are designed to haul a load. I was told that I needed to find the heaviest load I could and point it up the steepest grade I could find, and mat it. I live in the Colorado mountains so finding the grade was not a problem. The heaviest trailer was only 7K #s, and I would only mash it for short bursts, but it made a huge difference. I Have a Ramifier box, and I would use that to help load the engine, but kept an eye on the pyrometer, as it was very easy to get the EGTs too high in my thin air. I do not find that the box aids the mileage at all. It is more about fun, while I have found that replacing the airbox and exhaust, along with theTone Ring Mod. does help. My truck is basically the same, as it is an 04.5. and at 33K miles, I am flirting with 20mpg hwy, and probably 17-18 city. I have no gripes with that.

 

Twelve point seven ain't really bad mileage. Mine has improved since putting around 5000 towing miles on it over the past two weeks but it's not really much better than that.

There's "city driving" and there's "city driving". Some people's city driving consists of a few miles of urban interstate at 65 mph and a few blocks of traffic light/stop and go. Mine consists of about 1/2 mile without a traffic light or 4-way stop and the rest is constant stop and go at intersections. I'm getting about 13 mpg right now with this kind of driving and I'm not displeased.

 

I don't get much better then that in town either, 13 to 14, but I can get 20.3 mpg on the highway. The problem is I do most in town driving. I have 26,000 miles and have never towed anything yet.

 

Everyone with fuel economy complaints should at least tell their dealer about it so it can be logged in as a complaine. Its the only way they will do anything about it. I get 16.5 overall (with towing some 10k loads intermittently) and I still complained.

 

I agree with Lee S. There are huge differences in "city driving". I get between 12-14 in the central CT area where traffic lights seem to be every three feet and the highways during rush hour yeild 45mph max... if you're lucky.