04.5 M.p.g.

[KevinO]

Feel fortunate 700 I haven't seen better than 13 i towed a 16' flatbed with some lumber on it and got a little above 11. My 01 got way better mileage than this one too. Maybe the kitty needs to go on these trucks?

 

[Udaloy]

I think we need to know if those with poor mileage have auto's or manuals. My guess is that the ones' getting "good" mileage have manuals, and the poor mileage have auto's.

 

[klenger]

I averaged 80mph ... and got 12 mpg towing an empty 3000lb trailer. . left from Salt Lake... Arrived in Sacramento and picked up my load for a friend who is on active duty, CAT scales had me at 19,230 lbs total. I got 10 mpg at 65 mph all the way home... in fact in some flats it was showing 11. 2 average...

Those numbers don't seem that far out of line to me. I got about 10 MPG towing my 10K 5er with both my 01. 5 HO and the new truck.

 

[Udaloy]

Yes, that's why I think it's imperative to know if it's an automatic or not, the rear gear ratio, and the tire size. It's all related to the mileage.

 

[TX Gooseneck]

I've got 7,000 miles on mine now and it's staying about the same - 14. 7 actual and around 13. 5 on the overhead. I drive hard but 98% is highway driving. If I drop behind a truck and catch their slipstream it goes up a little bit.

3500 quadcab, 6-speed. I'll check on the gears. Pretty sure I got the numerically lower (taller) gears.

Hauling an empty gooseneck on friday, approx 6500lbs I was seeing 11ish.

 

[doldenburg]

tx i know you . dave in foley mn. trailer is great havent used all winter tho. i see you have new truck. i did also. mileage about the same. improveing saw 15. 6 today

 

[DKiesewetter]

Originally posted by doldenburg

tx i know you . dave in foley mn. trailer is great havent used all winter tho. i see you have new truck. i did also. mileage about the same. improveing saw 15. 6 today

Worst. Grammar. Ever.



Doug

 

[Udaloy]

LOL Doesnt mater relly do it

 

[Tomeygun]

Originally posted by KevinO

Feel fortunate 700 I haven't seen better than 13 i towed a 16' flatbed with some lumber on it and got a little above 11. My 01 got way better mileage than this one too. Maybe the kitty needs to go on these trucks?

Did you get the reflash yet kevin?



Check you engine build date and serial # and call me

1-800-748-8005

 

[JWerkheiser]

OUCH

I think he was just funnin', d. o.

 

[Apence]

Is the reflash for all 600's or just ones built before a certain date?

 

[doldenburg]

prolly was-someone dident think answer was funny

 

[doldenburg]

tommygun, flash worked, runs great now. mileage seems to be improveing on overhead. 3500 miles on now, Dave

 

[thejeepdude]

OK so I have another potential buyer for my 2ng gen (after I just decided to keep it and ordered DTT/EDM) and one of my concerns about ordering an 04. 5 is the mileage. I don't mind if it sucks for a while breaking in, but my plan is to keep one of these trucks truck forever, and I don't want to be stuck with a 14MPG/hwy rig for the next 10 years when I'm used to the 19-20MPG I get now. Is the general concensus that this is just an electronics issue and MPG will go up with a reflash? If I sell my truck, should I make do without for the summer and wait for the '05's and see if the issue is worked out or just order right away and trust that everything will be hunky dory once I get some miles on the thing? How's the highway MPG improvement been with the TST box? I love my truck, but man it would be cool to have 4 more inches in the back seat and those fold out floors not to mention the big disc brakes all the way around... Decisions... decisions...

 

[klenger]

thejeepdude:



Here's my comments on the reported milage issue:



1) First, some of the reports may very well be valid, and Cummins/Dodge will get it right.

2) The engines are not broke in yet.

3) This is the first time in while that a new engine has been released mid-year (winter).

4) We are using winter fuel (less energy in the fuel).

5) Cold operating temps in the winter hurt fuel milage

6) Many new owners have not had a chance to drive an extended trip on the highway empty (best conditions).

7) When members brag about their high MPG calculations, they tend to quote the best numbers, not their averages. When we buy a new truck, we are looking at the averages becasue we fill it up every week or two. Therefore, the numbers from a new owner's truck will rarely be as high as someone quoting their best numbers.

8) Some new owners have very high expectations.

9) Members who have reciently traded up are comparing a new stock engine to a bombed and broken in engine.

10) What was the question?

 

[Apence]

Well I have a 04. 5 3500 with a 600 and a 6spd I bought it from a dealer 160 miles from me. I drove 55-65 mph on the way home and got 13. 3 mpg. I have now been driving around town which is a 60%/40% rural/city and am geting 13 hand calculated. My trtuck I sold to get this one was a 95 2500 ctd w/ a 5speed. yes it was lighter and had 68,000 miles on it but i got 19-20 doing the same in town driving im doing now and 22-23 doing 70 on the highway. I love my new truck and am happy i got it has no miss and runs and drives perfect but I am very disapointed in the mileage and as much as people say it gets beter when i breaks in thats true, but I have only ever seen about a 2mpg increase. I think it has a lot to do with the lower emmission standards and what they had to do to achieve them, and i dont think that its going to improve any in the 2005 model year. Just my opinion

 

[DDahl]

When Cummins was discussing the future Dodge 4. 5 engine in Diesel Progress (a couple of years ago) they said that the future ISBe (with EGR and VGT) had better low end torque and got better mileage than the (pre 03) 24 valve engines.



Now that DC got involved (saving themselves $$$) in mods to the then described 4. 5 engine I have not heard a single word from Cummins about the 600's improved mileage anywhere in print!



I fear that while DC saved a few bucks, by avoiding the EGR and VGT (that gives exhaust braking and low end torque bonus), they made the 4. 5 owners pay a significant mileage penalty. All that advertised new high temperature valve technology including multi-layer exhaust gaskets may be required because more heat now goes out the exhaust while less goes out the crankshaft.

 

[thejeepdude]

klenger, I've had the same thoughts myself about the mileage reports we see on here. Even I am guilty of saying "my truck gets 24mpg!" when in fact that was one particular trip, and not the average. Around town everone has a different amount of GO juice they're usin when they accellerate from each stop sign, hence city MPG will cary widely. I know mine's been in the single digits before (the tank after I installed 275's and also towed ~10K lbs). But when we talk about highway mileage, as long as the person mentions their average speed in their report, there's not too many other variables besides maybe incline and headwind. As Apence reported, I wouldn't expect to see more than 2-3mpg improvement with break-in which would bring a lot of these trucks up to about 17mpg, still short of what they used to be. If this is indeed due to smog related changes, I am trying to speculate as to whether these changes are software or hardware, the former being more easily remedied with a box. If I remember correctly, only 8 major components were changed between the 600 and previous 3rd gen engines, none of which seem like they're decrease efficiency by themselves. I don't think the CAT is an issue. Now I'm wondering if I'd be better off buying a non-CA 305/555 HO truck used and bringing it into the state. The general concensus seems to be that those trucks get the same sort of mileage that we've come to expect from previous generations, even tho I've heard several bad MPG reports from their owners as well.

 

[Vaughn MacKenzie]

With a larger pilot injection on the 600s I think that's where some of the "extra" fuel is going now, and isn't there a post-injection too?



And you California guys. . . I think the diesel fuel there is pretty sad. It seems when I drive to Sac and fill up in Cal my power and mileage drops noticeably. Better try some good fuel additive.



Vaughn

 

[doldenburg]

if i baby my 600 i can see 14. 5 empty hwy. all around stop and go is less. my stock 01 ho loaded to 15,000 will do almost as good. im going on a long run next week ,will see how it does.