I am looking to buy a Dodge Ram 2500 4X4 what year Cummins diesel got the best mpg. I would love to get the new model but it doesn't sound like the '08 get very good fuel economy. Thanks for the input.

 

Cummins 305/555 with 3.73's and an auto get the best 3rd gen mileage because of only two injection events and the auto's overdrive ratio compared to the manual. As far as second gen, I believe 12v's get better mileage than the 24v's. Hope this helps alittle.

 

I've got the '06 Dodge RAM 2500 5.9, with 3.73 & 48RE, EB with less than 2,500 mi, I'm averaging about 17mpg., there are those out there getting >20mpg.

Rather than start another thread, what do you all recommend for a module upgrade to improve MPH and/or towing capability? Will the SMARTY provide this capability?

I'm not looking to add too much HP as I'm not looking to replace my auto trans, at least for a few miles

Thanks!

 

From what I've read on here and experineced first hand, the 2003 SO w/3.73s and the auto is probably tops, at least as good as the 12v anyway. The '03-'04 (but not '04.5) HO is really close. CRD but no Kitty. I've been very happy with mine. BTW, the stock Michelin's are goofy looking but return great MPGs.

 

I have a 95' 2500 4x4 5spd with 3:55 gears and get 20mpg out of it. From what I have heard the fuel economy has got worse and they have gotten newer. The best is 94'-98' 12v and then it went to the 98'-02' 24v, not to sure about the 3rd gens though.

 

I talked to a guy who said he got 24 MPG with his first gen 4x2, 5spd with 3.05 gearing.

 

well with my 1992 first gen i get about 20 hwy, but the PO got up to 26 once, and there is one guy on here who got like 27.? but he has a standard tranny/3.07 gears.

 

Could you actually get a 1st gen with 3.05 gearing???

 

lgp9999, yes but they only came in auto versions in 89-91.4 or special order.

rcs, in my truck I wrecked, I got 18 city. That is when I kept my foot out of it and had the pump turned way up. On the highway at 70 mph, I got 20 mpg. This is also with 4.10 gearing

 

without a doubt for the stock power those '03/"04 HO 305/555 Cummins with the NV5600 and 3.73 gears are hard to beat. My '03 with the above equipped, gets 22+ average on my 600+ mile a week commute and 12.5 average pullin' my 11200 GVWR 5er. All pencil figures. Add to that is the best oil change schedule out there at 7500/15000 miles.
JIM

 

Ditto those numbers, except with the auto trans.

 

My 99 w/ 3.55 rears, and std. 5-speed gets about 17.8-18.8 mixed driving, has been as low as 12 when towing 10K in the mountains, and as high as 21.7 when keeping out of the throttle, and driving 60mph on flatter terrain. That's w/ the FASS fuel system, K&N filter, and open exhaust.

 

I'm running 23.5mpg with the custom part time hub conversion. I was getting 18mpg before. I also switched to synthetic oil in everything at the same time of the hub conversion this probably brought the mileage up some.