Does anyone have any signifigant mileage on a 2004 1/2? What kind of MPG are you getting? I just bought one, 55 miles ago, and cannot believe that I will only get 9.5 mpg. A friend said that it took him approx 20k mi to start getting good mileage on his 2000.

 

You have a friend?

 

Yes, 20K for proper break-in is about right.

Still, 9.5 seems a bit low, even for brand new.

Couple things to check are fuel and air filters.
If they get clogged up it will show up as bad mileage.

Might be worth it to take it back to the Dealer and see what they say.

Not that familiar with 3rd gen's and the fuel system.


phox

 

Are you basing your fuel mileage on 55 miles of driving? Is that from the overhead, or topping off a tank? Or...?

Was the 9.5 from a friend? Maybe I'm missing something...

Its easy to read about all these high mileage vehicles and automatically think those top numbers will apply to all of our vehicles equally.

But like anything else, mileage depends on many factors, mostly driving habits. Lots of throttle, jack rabbit starts, cold weather, frequent short trips all contribute to the sucking of fuel like its going out of style. My truck can be a Dr Jeckyl and Mr. Hyde too. Keep it under 2000 rpm and she's pretty miserly for a big truck.

Its also tough to top off the tank consistently (foam issues) to get an accurate reading in a short period of time.

Hang in there, drive it for a while and get used to her. You'll get the idea on what she likes. You don't have to wait for 20k miles though.

 

3000 miles so far 17 city 19+ highway staying under 2000 rpm.

 

2300 miles and 19+ reading on trip computer slightly higher actual first tank was 15.5 but that was the only one that was poor

 

kbagg, is your truck a dually 4x4? If so I don't think it will get much better than 13mpg.

 

why's that?

 

Because it is the worst possible combination for mileage...especially if 410/auto. But who knows...once mine gets 100k mi. maybe it will get better than the 13mpg with 5000 mi. now.

Bulabula...what mpg do you get with your 2003...it seems alot of people don't believe or understand that the mileage on the 600 is alot worse than the previous models. Some of the people that vote on the polls are probably 305/555 owners. It is hard for me to believe that, after playing with mine, that any 600 will get 18+mpg.

 

My first tank was 15mpg. Now with 3500 miles 17 city, 19 highway.Not much differant than new 03's and 04's.

 

I work on 5.9 cummins all day long on heavy trucks and ground equipment. Break in depends on many things but we dont expect to see stabilization of fuel burns until 10-15000 miles, maybee more. Be patient, it'll creep up but these 600's may not reach the decent mpg's logged by the 03' versions. If not impressed by mpg's remember we cummins owners are driving powerplants that can easily go 500,000+ miles before major maintenance, easily #1 regarding durability.

 

I agree the 600 is not a bad engine I'm very pleased with mine milage is 5% below my old 99 but the power is 20+% greater. More fuel has to be burned to get that power, but the tradeoff in milage is not that great. The main factor in mpg is how you drive I suspect that the people with poor milage on the 600's had poorer milage on previous engines than I ever did.

 

jaycoje, I almost got the same truck set up that you have...color and all except it was an auto...I wish I had...but I wouldn't think the DRW would make that much difference. I guess each engine does different but I wouldn't think 5 or 6 mpg different. If you can imagine the easiest driving style possible and speeds not exceeding 65mph...I only get 13 to 14 with 5000 miles on it...and that is with afe air filter, straight pipe, homemade torque tube, and 65psi in all tires. When I get a few more miles, I am going to synthetic fluids and that is my last straw until a good box comes out. I would like to see a box that stops the annoying clatter and improves mpg.......and gives power when you want it.

 

Dwhite,I dont know if this helped but before my milage jumped up I towed my fithwheel around a few days.(about 9000 pounds) it felt smoother, shifted better and milage went up about 1-2 mpg's.

 

I have a 600 with 2000 miles and it is getting 11 - 12 around town pulling a 4 to 5000 lb. trailer. That is at least 2-3 mpgs better than the 2003 1500 4.7 gasser that I traded on this 2500.
With about 1500 miles on mine I drove about 150 highway miles at 75 mph and got about 17.5, at least 3 - 4 more than my gasser.
I can tell with only 2000 miles on mine it feels "more broken in" than when new.