6.7 Fuel MPG

[DSpivey]

well mine is averaging bout 9mpg with 35s and a 4 inch lift. thats in town just creeping along. im not happy at all . my duallie 04 by the way with 33s and a quad chip got 14 in town all day long. so im not impressed at all. im thinking there is something wrong. if it dont get better quick im going to dealer this is bull

 

[DSpivey]

the more i think about im pretty sure this thing is gonna be gone. im gonna go pick me up an 5. 9... ... ... .

 

[CUMMINZ]

Dp

What rear end gear are you running?

 

[DSpivey]

3. 73 Gears

 

[2Rowdy]

hey, I'm new hope I do this right.

I have had my 6. 7 for a month got 4500 miles on it. avg 14. 4 mpg all types of driving.

 

[Wolfy]

hey, I'm new hope I do this right.

I have had my 6. 7 for a month got 4500 miles on it. avg 14. 4 mpg all types of driving.

What rig?, Axle ratio?, Load?,Towing? (nothing in your profile)



Moving 8,000# is not the same job as moving 16,000#.

 

[jimnance]

Gosh, I'm feeling pretty good right now about the pristine 1st gen that I picked up for 5K. It gets 19-20 MPG no matter what I do. It will go 80 MPH though it may take a bit longer to get there. The injectors pretty much last forever as does the fuel pump. Hmmm.....

 

[ChipD]

Took delivery of my 07 3500 with 6. 7 at the end of April. My worst mpg has been 14. 6. Average has been 16. 8 with the best thus far 19. 8. Have just over 8000 on it now. According to several owners, mpg goes up after 10,000

 

[mcandies]

Mine started out with 12. 4 on the first fill-up. Just filled up today with a little over 5000 miles on it now and mpg is up to 14. 9. Things are looking up.

 

[2Rowdy]

Sorry, I have filled out my profile now.

 

[SGrimes]

New on 6/16. On a short (200 mile) road trip 6/23 averaged 17. 3. This was empty, with a thin wife.

 

[BHolm]

I'd be willing to bet the milage comes way up after the trucks are WELL broken in. My 5. 9 Mega started out getting 13. 5 mpg, mostly rolling mtn two lanes at 60-70 mph, some light city, 48re, 3. 73. At 46k miles I was getting 20. 1 doing the same driving. I did a bunch of heavy pulling with it and I think that helped. As to the altitude thing, I also live at 8000 ft and I found that my truck does slightly better (1-1. 5 mpg) at altitude than in the midwest, just my experience. I also saw identical max boost numbers, 30-31 psi regardless of altitude. I would agree that the truck definately feels stronger at low altitude though.

I am now running and '06 G56 QC LB 4x4 and getting 18. 7 over the last four tanks. The truck has 73k on it. Be patient, tow heavy, the milage will come

Point is, the 6. 7 isn't starting out any worse than two of my 325/610 5. 9s did. The '05 was getting 17. 8 by 36k, the Mega 20. 1 @46k. Nothing tops the one that got away though (glad I'm not the only one!) I had an '03 QC SB 4x4 48re 3. 73 305/555 on 285 BFGs that would get 23. 5 in the same driving as the the other trucks. Should have hung onto that one

 

[RVTRKN]

Gosh, I'm feeling pretty good right now about the pristine 1st gen that I picked up for 5K. It gets 19-20 MPG no matter what I do. It will go 80 MPH though it may take a bit longer to get there. The injectors pretty much last forever as does the fuel pump. Hmmm.....

1st gens are awesome trucks w/CTD but they are butt ugly, 5K though seems a little high. Did you check the blue book before purchase and is it a low mile truck? I noticed you have Gens I, II & III in your garage, must be a large garage.

 

[Vaughn MacKenzie]

Most 1st Gens are ugly, but a pristine one is a real looker IMO.

 

[JHilden]

My MPG

I have about 1,700 miles on my Ram 2500 with the 6. 7L. I have fueled up seven times, and my fuel economy from the last six times was 12. 4, 14. 4, 14. 7, 14. 8, 14. 9, and 15. 1. I keep track of all my fuel purchases and mileage on an Excel spreadsheet.



I have not received the new "flash" for the PCM, and lately I'm blowing a lot of soot out of the tailpipe. Hopefully when I get the flash it will help the MPG a little.

 

[Doughboy21kd]

With all this talk about fuel mileage... . I am wondering what you guys are getting for mileage turning 35" tires like i am... . Cause i know turning bigger tires is gonna hurt a little more than turnin the stockers... . Just kinda curious... . Trying to figure out if i am one that needs the Flash for bad MPG's or not... . As my mileage isn't so good.....



So those of you out there with bigger than stock tires i hope you see this and respond...



THANKS

 

[mcandies]

With all this talk about fuel mileage... . I am wondering what you guys are getting for mileage turning 35" tires like i am... . Cause i know turning bigger tires is gonna hurt a little more than turnin the stockers... . Just kinda curious... . Trying to figure out if i am one that needs the Flash for bad MPG's or not... . As my mileage isn't so good.....



So those of you out there with bigger than stock tires i hope you see this and respond...



THANKS

The tech at my dealer told me it was to increase burn times for the DPF. TSB says nothing about helping MPG.

 

[RVTRKN]

With all this talk about fuel mileage... . I am wondering what you guys are getting for mileage turning 35" tires like i am... . Cause i know turning bigger tires is gonna hurt a little more than turnin the stockers... . Just kinda curious... . Trying to figure out if i am one that needs the Flash for bad MPG's or not... . As my mileage isn't so good.....



So those of you out there with bigger than stock tires i hope you see this and respond...



THANKS

Shouldn't you get better MPG with bigger tires untill you tow or pull steep grades?

 

[Wolfy]

Shouldn't you get better MPG with bigger tires untill you tow or pull steep grades?

Yes, but without re-programming/re-gearing your computer (EVIC) or odometer, to factor-in the increased tire circumference, you will have no indication of the increased mileage.



Some on-road measurement should give a factor to use in hand-calculations, which would then be accurate.

 

[ModifiedDiesel]

Bigger tires will get you a lower overall gear ratio so lower RPMs, but your tire resistance tends to go up. Usually the net is a loss of 1 or 2 mpg in my experience.