Hey Guys , I'm look'n at the 08 6.7 in a 2500 4x4 qc. What kind of milage are you getting with your 6.7 4x4s on the highway. please list any mods and if its manual or auto. Looks like some guys are having some issues with the 2007.5 6.7s, are the 2008s having the same issues or are they getting the bugs worked out of em.
P.S. Please list the miles you have on your truck also.

Thanks Chris

 

No help from me on the mpg thing butI do know they detune the HP slightly on the manual equipped 6.7's.

 

Welcome to the forum.

I have 9500 miles on my truck since June. It is bone stock and getting 14-15 city and 16-17 hwy with 3.73 gears. I've had one CEL at 4700 miles which resulted in a new turbo. It was down for three days. I have not had any problems with the DPF. Dodge has been putting out new ECM flashes every couple of months, so they are working on the issues. Some have had better luck than others though.

I test drove the manual before buying the auto. IMO, the manual was geared too low. I found the six speed auto to be a vast improvement over the previous four speed auto that I had in my 2004. It is smooth and powerful. Test drive both and decide for yourself.

Good luck.

 

I have a 2007 with the 6.7L and G56 trans. I get15-16 MPG from mostly highway driving, with about 9,000 miles on the clock so far. My only engine mod is an Edge Juice w/Attitude, which is normally set to zero (stock). The 'Mileage' setting on the Edge seems to give me worse milage than the stock setting.

The G56 with 3.73differentials is definitely geared quite low. Some say it is similar to having 4.10 diffs with the automatic trans. At 70 MPH the engine is turning about 2,250 RPM in sixth gear.

 

Our 6.7 was a manual. 1st gear is useless...unloaded I could get it moving from a dead stop w/ no problems in 3rd. Our milage sucked but I don't think we ever broke it in either.