600 fuel economy

[TCordero]

I am soon to be a new 600 owner, first time diesel owner. I bought the diesel for the fuel economy, the guys I work with who are driving the cummin's are getting 19-21 mpg. Should I expect the same from the new 600? Any suggestions on low cost upgrades to increase the mpg?

Thanks



On order: 4x4 quad, SLT, LB, 6 spd.

 

[TX Gooseneck]

In short, you won't get that kind of mileage. They are working the kinks out, but with mine (2wd, quad, 6speed dually) I'm seeing a best of 17ish IF i stay under 70. Much better than a gasser would get. I've had the reflash done as well, before that I was getting 14. 4mpg.

 

[redram]

Improved Mileage

Lose the 4X4 if you really don't need it.



Extra weight and rolling friction of all terrain versus highway treaded tires.

 

[klenger]

Welcome to the TDR. You'll like the truck. I'm getting up to about 17. 5 MPG empty with 3400 miles on it. I expect it to get a bit better over time. I just had the reflash done today. Your truck will be built with the new software, so don't worry about the reflash.

 

[EXSTROKER]

STOP DONT DO IT

The guys that are getting good milage are lucky

most of us with the 600 arent so lucky...

I get a best of 13 mind you that is with no trailer,tailgate down

7-9 pulling this is a flop for cummins... but if ya want i will sell you mine...

 

[favord]

My mileage is similar to Exstroker's. Typically single digit mpg pulling my horse trailer. Much worse mileage than my 98 and of course less power. Not sure I'd buy another one.

 

[thejeepdude]

Originally posted by favord

My mileage is similar to Exstroker's. Typically single digit mpg pulling my horse trailer. Much worse mileage than my 98 and of course less power. Not sure I'd buy another one.



98. 5, 5 spd. , BHAF with IAT, TST PM3, Bully Dog II's, Centerforce clutch, U. S. Gear exhaust brake

Hmmm... BD2's and TST PM3... I wonder why the new 600 doesn't have an much power. As for the mileage, that does suck. Have you, favord and exstroker, had the reflash done? If not, let us know what happens when you do. If so, that is really sad. Just for curiosity sake, why don't one of you guys with the REALLY bad mileage take your CAT off and see what happens? So far only one person that I know of tried that on here, but his mileage wasn't as bad as yours... if I had one that bad, I'd be going over the whole truck with a fine tooth comb... gears and all the drivetrain... to make sure there's not something setup wrong. Intake and exhaust of course... maybe there's a rat in your downpipe and the cat won't let it out! It just doesn't seem to me that cummins would let something out the door that dropped that much in efficiency, unless it's just a limited serial number range and there was an upset empoyee wreaking havoc in the factory that day. I mean, it's the same size motor, and no matter how you look at it, wouldn't the same amount of fuel be required to make the same HP and hence same MPH therefore MPG... man I wish they'd figure this out... before I order mine!

 

[MVaden]

My milage is 11. 5 in town and about 13. 1 on the highway and thats with no towing or load And about 1700 miles on it so far. No reflash yet.

 

[CoastyAV8R]

So far I have gotten 14 mpg in the first 500 miles, then I towed our trailer 300 miles with it getting 10 mpg. Since then the truck has been averaging 17. 5 driving back n' forth to work. I don't haul ass, I go 70 on the highway and whatever the speed limit is elsewhere. I drive the truck like I want it to last for a while. I ensure the air pressure is correct in the tires and while breaking it in, I did as the owners manual said. This is my 3rd Dodge/Cummins truck. I have had one of each generation. This truck so far is doing just fine on mileage, is a much stronger puller than the other two (both stock) and is a far better ride. It sounds like a few guys have had fuel mileage issues with their trucks for whatever reasons. Whether it's the truck or driving habits, they are unusual and not the norm. I wouldn't flinch because a few guys get bad mileage. There may be some software issues with some of the trucks that seem to have been ironed out. Regardless of what some people have said, the Cummins engine is a proven performer, if there are some glitches, you can rest assured Cummins has addressed them. I haven't experienced any in the last 10 years of owning and driving these trucks.

 

[DocDetonancour]

Guy on the other 3G posts picked up his truck in Vegas and got 18 + from day one? I've got as good as 20. 5 on my 04. Good luck, Doc

 

[favord]

Yah, jeepdude, it's not really fair to compare a bombed rig to stock in terms of power. The 600 really does do a great job of pulling my trailer for a stock rig... just sucks alot of fuel doing it.



If I could do it over, I'd probably go for a 2002 dually 6 spd. with low miles, 10-12K cheaper, bomb it like my old one, and drive like mad for 100K miles.

 

[DFeinauer]

I just fill the tank up tonight, Best MPG so far, 14. 54 MPG City/Hwy 50/50 I have 850 miles on truck. Its better then the last tank by 3 mpg both times hand calculated and fill to fill neck. I sure hope it keeps improving.

 

[EXSTROKER]

yup im going to start taking stuff off and see if thair is a difference

I have about 6k on mine afe air that is all so far

 

[OCarney]

Had my 600 for a week. Most driving under 70 mph, not towing or hauling. 1st tank 17. 04 MPG hand figured. Mine is 3500 quad 2wd and 6 speed, no mods yet.

 

[Pawpaw]

Originally posted by OCarney

Had my 600 for a week. Most driving under 70 mph, not towing or hauling. 1st tank 17. 04 MPG hand figured. Mine is 3500 quad 2wd and 6 speed, no mods yet.

For what it's worth, that's better than my 555 did the first week. I got about 15. 5. Now (11,000 miles) it's doing much better. I have seen as much as 20. 5 on a tank that was half interstate and half in-town highway.

 

[jwilliams3]

14 mpg here.

Foot in it all the time, had 13mpg first tank.



--Justin

 

[vagabond]

If you travel E/W I80from Neb. to Ill. or I76 in Colorado you may have seen me in my 04. 5 with the 600. I pull a two car hauler and maintain speeds within the max limit. I bought it in Feb. New and now have 14000 miles. The truck is on the road most of the time. I broke it in as recommended in the book and then let it go. Hauling I would get 7. 5 to 8mpg. With the trailer empty 10. 5. I am now getting the 10 to 11 range with a full load and without the trailer 17 to 17. 5 highway with a average over all city and highway 15. 4mpg. I have found the fuel I use makes a big difference. When I fuel at the truck stops and use #2 diesel I do much better than with the so called premium fuels you get at the local station. I am new to the forum and have gained a lot of valuable info from reading the posts. I hope this will give you some hope for improvement with your milage

 

[CoastyAV8R]

I noticed that when I was in California, as soon as I got fuel out of California my mileage would go up 2-3 mpg...

 

[klenger]

vagabond



Welcome to the TDR. I am curious if you found the power and responsivness improved as you put more miles on it?

 

[vagabond]

The truck is quicker and has a lot of power. I have the automatic and with a full load it stays in o/d all through Neb. on I 80. With the hills in Iowa I use the tow/haul feature.