Jonesboro

I don't think you are really interested in participating in an objective discussion of the MPG issue. And you've clearly demonstrated that you are not open minded about the experiences of others. I actually believe that I could have gotten better than my actual 28.77 MPG because later I checked my tire pressures and found them all to be low.

Your focus seems to be in discrediting others and proclaiming your superior knowledge.

Enough said, it's your thread now!

wexman

All right, usually I stay out of these things, but I have to "weigh" in here, and I DO mean "weigh".

Over on TDS, they were posting some comparable weights of trucks. I see that my truck, in the config below, has a curb weight of 7927 lbs , that would be over 8000 with just me in it, not to mention any kind of payload.

My previous truck, am F350 srw PSD, weighed in a curb weight of about 7300 lbs. That's almost a 700 lb difference.

My PSD got about 15 mpg in the same conditions that my 600 is getting about 12. The PSD also had 3:73s, to my current 4:10s. The PSD also was rated at 50 LESS hp, and 80 LESS lb ft of torque.

I'm really not expecting much more MPG from my truck. Weight + 4:10s + stop-and-stop commuting+my LEAD foot = iffy MPG. Still better than any gasser.

My $0.02.

Bert&Holli

I've watched this subject for years, it started (with the Dodges anyway) when we went to 24 valve engines, then with the common rail series, now the 600 motors. I am interested in an objective discussion, and have not claimed superior knowledge in anyway. What you failed to gain from the constructive points in my original post is that ALL series of diesels in ALL brands have a few that get inherently bad mileage. But your right about my close-mindedness about your claim, I just don't believe it and not afraid to admit it. Back to the subject at hand...It just seems that alot of folks are jumping all over the 600 for no reason. Again, I understand some are having terrible mileage, hopefully DC will figure something out, and I don't think build date has anything to do with it. It could be a million different things like extra tight axle or transmission components. Or maybe the engine is just a little tighter than most and will take alot longer to break in, I'm reaching here but we need to get everything out on the table. Has anyone with bad mileage checked their pumpkins to see if there are unusual wear marks on the ring or excessive metal shavings? Any extra resistance will knock the mileage down considerably, as a slight headwind knocks mine down 3-5mpg.

Edited by Admin

Lary Ellis (Top)

I asked you guys nicely to bring this down a notch and be nice, Now I am telling you that personal insults here will not be tolerated.

Anyone who wishes to continue slinging personal insults here will be immediately removed from this site permanently!.

If you can't make your point without being ugly to someone, you are not welcome here.!

Think before you post!

stevenknapp

I've watched this subject for years, it started (with the Dodges anyway) when we went to 24 valve engines, then with the common rail series, now the 600 motors.....Again, I understand some are having terrible mileage

Same boat, and I've noticed that for each generation of trucks there are a few people here or there that get bad mileage regardless of the configuration. And a few that get really great mileage. There has been more than one post here in a 600 MPG thread that said something to the effect of "I wish my 2nd gen got that good of mileage".

I'm not sure it's a 600 issue, tho I'd expect that the 600 would get a MPG or two less. The NOX reduction is supposed to come from cooler combustion, either from EGR or different injection timing (not just the third event). In an SAE presentation it was mentioned that the issue with the altered injection timing, vs the cooled EGR, was slightly worse fuel consumption. This is just one factor of MANY. So it may be that that loss was made up for somewhere else. Or not. I don't work for Cummins, I didn't develop the engine. But if the 555 got between 14-26, the 600 still sane at 12-24.

I believe the 26MPG claim, but I'm curious if it's repeatable. Or if it was just from that one trip? I've had trips where a tailwind got me 3-4 MPG, that and keeping my foot out of it added up to some really high MPG.

Vaughn MacKenzie

Bert & Holli, I back up Jonesboro's experience because I have personally witnessed 2 different Rams that have run the kind of mileage figures he's experiencing. One is a '95 12-valve automatic regular cab belonging to the wife of MikeR on NW Bombers. On a trip from Seattle to Bellingham and back he set the cruise on 70 and when they arrived back at home they filled up and topped it off well and calculated the mileage at 28.6 MPG.

Evan A Beck of NW Bombers regularly got 27 MPG with his 98 24-valve regular cab auto and often went over 700 miles between fillups.

Take it as you wish but it's a fact some trucks do get that kind of mileage, all while driving normal highway speeds.

Vaughn

Barrett_Fodder

Sure wish i could get my hands on a few of those trucks getting upper 20's and do a tear down of their's and some of the ones getting low 10's just to see what the difference is. See if things "mic" differently such as was suggested earlier. I get around 15.7 - 16 in town and 17-18 on interstate sometimes i get 19-20 depends a lot on the headwind but i have hit 21.7 on a 800 mile trip which is my best to date. I could see a few mpg differences from tolerances but to have some get 13 and others get over 2 times that is just amazing. Imagine if one persons little car got 45 mpg and their neighbors same car got over 100 mpg i think there would be some serious question asking going on. I believe it is possible to get incredible fuel economy from these engines. I think synthetics, free flow intake exhaust and elimination of the 3rd injection event (600's) as well as some serious tuning in the timing department and perhaps a little head work could gain a total of about 6-8 mpg, perhaps even more. If anyone has done something to their vehicles that they noticed gained a legitimate (read: you keep good records) gain in mpg please throw it out here and lets see if we can maybe help each other out.

Jonesboro, did your truck get such good fuel economy right of the shelf? Have you added any aftermarket components? Do you run synthetics or fuel additives or anything? I would love to consistently get up into the 20s..

Good thread lets keep the input/feedback coming...

Jonesboro

Guys, I assure you that the 28.73 MPG I reported in fact actually occurred. I have not fabricated this in any way and there were no unusual conditions involved. Also as I reported I subsequently determined that my tire pressures were at 42psi and I believe that the recommended 50psi would have yielded even better MPG. Here is a copy of the complete post I made in another thread on this site that includes a few more details:

"I just completed a cross country trip last week and had a chance to check my MPG. I was not towing anything, I had no load, and I was the only person in the vehicle. All MPG calculations were by hand and I filled the fuel tank to the top of the neck (took a lot of patience and squeezing). BTW the cheapest diesel I purchased was $1.49/gal in Kentucky.

This was all freeway driving. I set the cruise control on 1850 rpm which is about 63-65 mph in 6th gear.

I ran the first tank from full until the low fuel lamp came on:

752 miles, 29.429 gals = 25.55 MPG

The second run was intentionally a shorter distance but again filled to the brim at start and finish:

312 miles, 11.806 gals = 26.43 MPG

The third run was as above:

469 miles, 16.321 gals = 28.73 MPG"

The details of my truck are of course in my signature. It was manufactured in 11/02. It is a bone stock truck with 8000 miles on the odometer, no synthetics, no additives. I purchased it used so I do not know its MPG when it was new. It has had the Safety Recall #C02 reflash for the cruise control and nothing else done to it as far as I know. It still has the cracked alternator bracket which I need to replace. I consider myself very fortunate to have this truck.

J&L

KATOOM
My '03 gets 1-2 mpg better than the '01 I had and much better towing performance. The '01 was 235/460 auto, 3.54, s/b, quad and 22 mpg was best i got on road trip empty.
The best mpg, with pencil, my '03 has gotton is 23.8 mpg on road trip and empty truck.
Best towing, 11200 gvwr 5er is 13.5 @55-60mpr.
Worst towing same 5er was 11.5 @70-75 mpr on interstates. These were with my '03 .
I didn't have the 5er when I had the '01 so I can't compare.......JIM

csmo1026

hey guys, im glad i found this place.. i was getting ready to buy 2 new duallies 4X2 6 speed with the cummins and i found this site while doing some last minute research. I am selling my ford f450 mainly because of the 6 m.p.g. i get while towing. I tow 12000 lbs about 100k per year. the cost of fuel is putting me out of business. i thought i found the cure with 2 new dodges, but i am horrifed to hear the stories about the 500 vs. 600. How can I make sure i am buying 2 500's? are they still available? will it say on the window sticker which it is? if i cant get 10 m.p.g. while towing 12000 lbs, i am in trouble... HELP !!!

dwhite

The MSRP price for the diesel option (on the window sticker) is 5225.00 for the 305/555. The 325/600 motor MSRP is either 5360.00 or 5460.00. There are still alot of 555's available in Texas and probably other states.

Go to www.dodge.com and do a dealer search and you will be able to pull up each truck's individual window sticker.

Barrett_Fodder

csmo1026,

I wouldnt fret over your decision much either one is almost a sure bet youll get better than 10 mpg. I have 2 4X4 Quad Cab Long Bed Dually 03's that both get about 13.5 - 14.7 mpg towing anywhere from 9000#'s up to an estimated 13,500#'s. Keep in mind that is the trailer weight and both trucks also have 3 heavy toolboxes loaded down on them. The 600's early builds at least still get better fuel economy than either the ferds or chebies could get. The newer builds seem to be doing better still. I wouldnt have it any other way we have put a total of about 85,000 miles on the 2 trucks in the last year and have spent only about 35% of what we spent in gas last year for our 2 V-10 Dodge 3/4 tons. Definitly cut operating expenses. (Gas was a lot cheaper last year too) uggg

KATOOM

Thank you! Not really sure what happened.

mymaur

THis whole mileage issue with the 600 is such a hot topic that I am sure one of two things will happen. Either Cummins will fix it or there will be an aftermarket solution.

stevenknapp

THis whole mileage issue with the 600 is such a hot topic

Is it just with the 600? Or is it just that the 600 is new, and hence we think this might be a problem.

I've seen a good number of folks with '03s, heck even 2nd gen 24V trucks post really bad mileage.

And I've seen a good number of 600's post with good mileage.