Couldn't be happier with my 600's mpg

[JEgan]

I just filled my new ram up for the second time (at $2. 11 a gal. ) and after 750 miles of city driving, I am getting 14. 3mpg. I am happy as I can be with my mileage and with this machine. After reading many ram owners in this forum complaining about their individual mileage, I was somwhat anxious about what my mileage would be before I took delivery. I have to say that IMHO the disparety in mileage between individual owners has got to have a lot to do with how you drive these things. Gentlemen (and ladies), these are trucks! They weigh well over seven thousand pounds! and they are capable of pulling a house off its foundation! You cant expect them to get mileage like a golf cart. When I think of the capabilities of this machine and that my truck, with all that power on tap, can still get 14. 3 in city driving and, I might add ride like a car, I am amazed. I dont mean to rant, but this is one Ram 600 owner who is very happy.

 

[KBertetto]

Glad your happy with your rig. Mine started out just under 15 mpg in town and now after almost 8k miles (4k towing 10k 5er up Alaska Highway) I get a consistent 16-17 in town and turn a consistent 21 on a good stretch of highway (if I keep my foot out of it). I'm really happy with that, but there are some fellas that are getting absolutely terrible mileage out of these things. Lucky I got a good one I guess.



Bert

 

[jcarey]

Us, too. I broke it in very slowly, varied speeds, no higher than 45-50 for first 300 miles. Then no more than 55 up to 1000. I know folks would argue with my mehtod, but our first tank was 17. 04. Lowest was 16. 97, highest was 19. 01 with mixed driving about 60% highway - 40% city. All calcs are done by Mr Excel. I make mistakes using a calcualtor (go figure... )

 

[Fireman]

Yep !

Mine gets 17-19, not bad for a 4+ ton truck that'll haul almost anything. Couldn't be happier



It really disturbs my wife, her 1500 with a hemi only gets 13-15.



Fireman

 

[Nine Ball]

I'm still on my first tank, down to a half tank now and it has been averaging 16. 5 on the overhead and 17. 1 by hand. I'm very pleased with this 2wd dually so far.



Anything over 15 is good for me in a truck this big!

 

[RTuvell]

Originally posted by JEgan

I just filled my new ram up for the second time (at $2. 11 a gal. ) and after 750 miles of city driving, I am getting 14. 3mpg. I am happy as I can be with my mileage and with this machine. After reading many ram owners in this forum complaining about their individual mileage, I was somwhat anxious about what my mileage would be before I took delivery. I have to say that IMHO the disparety in mileage between individual owners has got to have a lot to do with how you drive these things. Gentlemen (and ladies), these are trucks! They weigh well over seven thousand pounds! and they are capable of pulling a house off its foundation! You cant expect them to get mileage like a golf cart. When I think of the capabilities of this machine and that my truck, with all that power on tap, can still get 14. 3 in city driving and, I might add ride like a car, I am amazed. I dont mean to rant, but this is one Ram 600 owner who is very happy.

I'm glad you are happy with the MPG of your Cummins 600, but I think you are missing a major point why other 600 owners complain about the MPG issue. The complaint is that the 600 (3rd Gen) gets noticeably lower MPG than an equivalent 555 (3rd Gen). In other words, 600 owners were surprised to find that their MPG was lower than what had been reported by the average 555 owners and there was no reason to expect this lower MPG to occur. No one likes negative surprises.



Don't get me wrong, the Cummins 600 MPG is still respectable in such a relatively heavy vehicle. I just hope that Cummins owners don't start "lowering their MPG expectations". I'd like to see the heat stay on DC/Cummins to work hard to regain the high MPG that we know from experience the Cummins engines can achieve!

 

[Winston Wolf]

Toyota vs. CTD

FWIW, my Toyota Tacoma with a V6 consistently gets 17mpg in mixed driving. I got 17mpg before adding a supercharger and after (unless I get on it ). But the supercharger requires premium gas.



Considering relative size and capability, the Toyota mileage is rather disappointing.



Doing some rough calcs on the price of diesel vs. gas, it looks like the breakeven point on total fuel cost for a given amount of miles is about 2mpg. So if I got 17mpg in the Tacoma and 15mpg in the CTD, my overall fuel cost would be about the same.



That makes the CTD look pretty good in my book.

 

[klenger]

Here's a poll I posted reciently on the 04. 5 600 milage



https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=103763&highlight=poll



and here's one for the 3rd gen non-600's



https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=104946&highlight=poll



Comparing the results is interesting, but inconclusive. With the exception of the high number of votes for 20 or over for the non-600's, both engines milage peaks out at 17 MPG with a pretty "normal distribution".

 

[bombero]

Well I am going have all three of them, all new . My 92 4x4 5sp 3. 54 got around 16 in town and 19-20 on the highway at 75+. My O1 HO 6so got about 14 in town and 16 on the highway until I added a EZ and that increased about 2mpg. The EZ realy helped it. The EGT fell 300 and the mpg and the power went way up. Waiting for my 05!!!

 

[stevenknapp]

The complaint is that the 600 (3rd Gen) gets noticeably lower MPG than an equivalent 555 (3rd Gen).



This is what I keep wondering about. I've been reading the TDR on and off since about '95. I've always noticed that there are folks who get high MPG, and those who do not. except for klenger's surveys there isn't much data. Even the TDR FAQ they mail you says something like 14-20 empty.



It's interesting reading the "my 600 MPG sucks" threads and finding posts in there from "555" owners saying basically 'ya! I was expecting more too, I'm only getting 17".



We'll see. I'm not convinced there is any hard work needed here. I'd rather they keep working on the '07 solution.

 

[RTuvell]

Originally posted by klenger

Here's a poll I posted reciently on the 04. 5 600 milage



https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=103763&highlight=poll



and here's one for the 3rd gen non-600's



https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=104946&highlight=poll



Comparing the results is interesting, but inconclusive. With the exception of the high number of votes for 20 or over for the non-600's, both engines milage peaks out at 17 MPG with a pretty "normal distribution".

I agree that the results of your poll are inconclusive, but then all Internet polls such as this will always be inconclusive.



Nevertheless, the fact that close to 50% of 555 owners in your poll reported 20+ MPG whereas less than 6% of 600 owners reported 20+ MPG is definitely worth noting!

 

[RTuvell]

Originally posted by stevenknapp

The complaint is that the 600 (3rd Gen) gets noticeably lower MPG than an equivalent 555 (3rd Gen).



We'll see. I'm not convinced there is any hard work needed here. I'd rather they keep working on the '07 solution.

If you are referring to meeting the 2007 diesel emission standards then many people believe there is a direct relationship. The popular speculation about the drop in MPG for the 600 is due to the approach DC/Cummins used to meet the lower emission requirements beginning in January 2004. "So far" it appears that there may be a tradeoff in performance (MPG) required to achieve lower diesel emissions. Hopefully DC/Cummins will ultimately find an emissions solution that does not sacrifice MPG.

 

[klenger]

Comments on the MPG polls mentioned above:



1) Keep in mind that the polls were for "best repeatable milage", not average milage. I think one of the reasons the pre-600 trucks have so many above 20 MPG is because they have had more opportunities to drive a trip or two under "ideal conditions". According the the poll question, you would only need to drive a couple of tanks above 20 MPG to qualify for "best repeatable". On my 2001. 5, I had one tank of fuel with just over 20 MPG. The way the poll was worded, I could claim 20 MPG. My average was more like 18 MPG, which is about 1 MPG more than my 04. 5.



2) The pre-600's have had longer to break in than many of the 600's.



3) The 600's have more power. If you use the extra power, you will use more fuel.



While I have no doubt that the 600's may have lower milage than the pre-600's, I think we will find that the numbers are more like 1 MPG less, not 4 - 6 as many are lead to believe.



That's all I have to say about that.

 

[RTuvell]

Originally posted by klenger

Comments on the MPG polls mentioned above:



1) Keep in mind that the polls were for "best repeatable milage", not average milage. I think one of the reasons the pre-600 trucks have so many above 20 MPG is because they have had more opportunities to drive a trip or two under "ideal conditions". According the the poll question, you would only need to drive a couple of tanks above 20 MPG to qualify for "best repeatable". On my 2001. 5, I had one tank of fuel with just over 20 MPG. The way the poll was worded, I could claim 20 MPG. My average was more like 18 MPG, which is about 1 MPG more than my 04. 5.



2) The pre-600's have had longer to break in than many of the 600's.



3) The 600's have more power. If you use the extra power, you will use more fuel.



While I have no doubt that the 600's may have lower milage than the pre-600's, I think we will find that the numbers are more like 1 MPG less, not 4 - 6 as many are lead to believe.



That's all I have to say about that.

I appreciate that you are trying to put a positive spin on a very sensitive subject. I sincerely hope that the 600 MPG issue turns out as well as your optimism.



We did not hear new owners complaining about poor MPG when the 555 came out. The MPG issue started with the 600. I believe there is a basis for the 600 owners to be concerned but we don't know the cause. I hope that DC/Cummins takes the issue seriously.



That's all I have to say about that.

 

[Sarge]

My 04. 5 gets about 3. 5 less per gal then my 01 HO did. But considering that the 04 pulls better than the 01 did with an Edge box on it, the 04 is a Quad Dually 4X4, and weighs nearly 2000 pounds more... ... ... I'm happy as can be. (and the ride in the 04 is WAY better than the 01) Sarge



Oh yeah, and That's all I have to say about that...

 

[CAgnoli]

I guess I'm still confused. I drove my truck 55mph yesterday to work and back (97 miles each way), 22. 4mpg. When I drive it 70MPH, I get 17. 4 to 18. 2 pretty consistently.



What I don't understand, is how the truck can use less fuel traveling the same distance, while running 15 minutes longer???



For example, at 55mph on the highway with the cruise on, my truck turns 1700rpm. That works out to 102000 revolutions on the trip. (1700RPM x 60 minutes) Yet, when I travel to work at 70mph, the truck turns 2000RPM equating to 90000 revolutions. (2000 x 45minutes) So I'm seeing the truck turn an additional 12000 rotations... ..... Why does it use more fuel?



Maybe I should stick to computers..... at least I understand them!



I agree that more pressure should be applied to DC and the EPA, it doesn't make sense to me why we should use more fuel to reduce the amount of emissions our trucks put out, the atmosphere has done a pretty good job of filtering out all of the industrial waste humans can throw at it, but some Volvo driving freak can state that we're killing the planet?



Lastly, if Edge and other companies can make a box that dials up performance, why can't DC include a switch on the dash that dials down the power for optimal performance? I'd be more than satisfied with the truck if I could push a button on the dash, and cut the HP by 100, when communting, and see low to mid 20's, and push the same button to tow a camper up a hill without downshifting. Just an idea.

 

[klenger]

Assuming that you are driving in the same gear, the engine revs to travel the 97 miles is the same. Revolutions per mile is determined by gear ratios and tire size, not speed. The reason for the lower milage at higher speeds is because wind resistance increases as the square of the speed. Example: Going 70 MPG creates 4 times as much wind resistance as traveling 35 MPH.



By the way, the numbers you are getting are excellent.



Do you have an auto or manual?

 

[stevenknapp]

If you are referring to meeting the 2007 diesel emission standards then many people believe there is a direct relationship. The popular speculation about the drop in MPG for the 600 is due to the approach DC/Cummins used to meet the lower emission requirements beginning in January 2004. "So far" it appears that there may be a tradeoff in performance (MPG) required to achieve lower diesel emissions. Hopefully DC/Cummins will ultimately find an emissions solution that does not sacrifice MPG.



Agreed, I think there is a small MPG reduction for the 600 emissions, but there is also more power. My thought was more that the '07 regs are a huge challenge. In the context of the OEM's aren't 100% sure if/how they are going to meet them in a cost effective way. Some of the ideas on the table really aren't too hot. Urea injection for example... MPG aside, I'd rather they come up with a diesel that meets those regs that people actually want to buy.



When I first signed up for the TDR around '96 I got an FAQ packet that said "Q:What's my mileage going to be? A: It depends... " and the gist was 15-20mpg was a common range for highway unloaded. 4x4, auto, or dually made those numbers a bit worse. And mileage would improve after break in. I got the same packet when I rejoined last year. I see plenty of posts with 555's getting 17 best case. Even some "My mpg just dropped 4MPG" threads too...



From what I've seen, with a few exceptions, the 600s seem to fall into that range. I wonder if it's a problem, or just hype. New motor, first few people to post had bad mileage... who knows. We'll see in a week or so how I make out.

 

[RTuvell]

Originally posted by stevenknapp



Agreed, I think there is a small MPG reduction for the 600 emissions, but there is also more power.

If the 600 actually produces more power than the 555 it is not showing up at the wheels. There have been a number of reports from dyno runs of the 555 and the 600 back to back on the same dyno showing no meaningful difference in HP or torque.

 

[stevenknapp]

If the 600 actually produces more power than the 555 it is not showing up at the wheels. There have been a number of reports from dyno runs of the 555 and the 600 back to back on the same dyno showing no meaningful difference in HP or torque.



"A number of reports"? I've seen a couple that show equal and I've seen a couple posted that showed increases as well. All were well used 555s vs brand new 600s.



Driveline losses vary from truck to truck as well.