I have a 2005 2500 Dodge Cummins with the G56 transmission averaging around 20 MPG. I just bought a 2007 DRW 3500 cummins with the 48re. I am only averaging around 15 MPG with this truck. What is the deal? Same exact 5.9 motor.

 

Manual to auto and SRW to DRW are 2 BIG reasons. Calculated or OH display? OH could be another reason.

 

Mine gets right at 20mpg on the hwy. A little better than my last truck with a
six speed. Around town its down to 15 to 17 mpg. Both with the Juice in the stock mode.

Dave

 

Wow Dave, yours does better than mine. In the city mine does about 15 (best was 18) and on the highway about 17

 

I think I've read posts here that even tho' they are both 5.9 engines, there are some differences in the emissions systems due to the switch to the ultra-low sulfur fuel between 2005 & 2007 - does that sound right? So it's maybe a combination of a lot of 'small' changes - auto vs manual, SRW vs DRW, etc, and perhaps some differences in the way you use & drive it - all together that could account for the change you are seeing.

 

Last time I went to my son's house in West Palm, I filled up the trucks main tank, unpluged the transfer flow system and filled up as soon as I got off the Interstate. 124 miles, 6.1 gallons. I used the first shutoff point on the nozzel
in both places.

When I have the Turbo Wing mounted its 15-16 on the hwy. I leave it off unless I'm towing the fiver.

Dave