4 things I can do to improve mpg on 600

[gsbrockman]

Originally posted by Ol'TrailDog





Trade it in on a 555 :-laf

:-laf :-laf :-laf :-laf :-laf :-laf :-laf

 

[ceaman]

Re: Whoa! Whoa! Whoa! Back it up a sec...

Originally posted by Crunch

Sorry man, but you can't just drop a "gotten the truck bought back" and "ton of problems out of mine" and expect that to slide without comment. You've got an `04 and you're already working on a buy-back--for a ton of problems??? Dude, you're gonna have to spend some time in the chair under the bright light while we interrogate you. What kind of problems are you having with your `04 that would cause you to move to the buy-back option so soon? Are they all truck related? Engine related? Dealer related? Cat related? We gots to know...

Mine has the same problem several people have has with the stuttering and lack of power that the re flash was designed to fix. The problem was noticed with 500 miles on the truck. The fuel mileage was terrible then and still is today. The check engine light has started coming on intermittently, truck has become hard to start in the mornings and there is a whine coming from somewhere in the drive train which is also intermittent.



The truck goes in tomorrow to address all of those issues, some for the first time others for the 5th or 6th time. They are trying to repair the engine stutter now for the 5th repair attempt but for tomorrow is scheduled for "further testing" not necessarily the repair. According to Star (Daimler Chrysler tech) the truck is one of 4 trucks in the U. S. that the flash did not repair, leaving me 14,500 miles of unhappy driving. The three other trucks in question had new fuel injectors installed which repaired two of them. This leaves my truck and one other truck somewhere in the U. S. without repair.



I have had more problems from this truck than I have had from any of the 8 DC vehicles I have owned in the past 4 years. I am a loyal DC customer who has a distaste in my mouth now. I hate to think that i might have to go to one of the other 2 choices but I am not making money if the truck is parked. I also cant take the hit on the pocketbook to pay for lower fuel mileage with the rising fuel costs. I put an average of 10K miles on per month on my truck, in dollars that is about $1850 a month in added fuel expense at current pricing.

 

[ceaman]

P. S. Can I have my 555 back?



:-{} :-{} :-{} :-laf:-laf:-laf

 

[Gizmo 007]

Not sure if it helps, but my new 4x4 600 is getting 16. 8 MPG on the overhead (16. 78 MPG figured by hand) and only has 1380 miles on it. That's right, 1380 miles! I pulled my 21 foot bass boat weekend before last and averaged 15. 4 MPG.



Mine is going in next week to fix a vibration in the front end. (front driveshaft). Anyone know of a way to convert it to manual front hubs? That would help the mileage factor drastically.

 

[Huntercrg]

remember a couple of months back, all guys that had just bought a new 555 were all crying and mad at dc because dc didn`t tell them they were coming out with the 600? I don`t here those people complaining anymore. Seems they think maybe they dodged a big bullet. well what they say is what comes around goes around. Maybe dc will comeout with a 700 in 2005 that will get 5mpg and all us fools who bought the 600 won`t feel near as bad. Hunter

 

[EMD-Run8]

Triple Nickle for me man!!! Hey---I like the way that sounds. Think I'll change my sig... ... .

Seriously though, I would definitely put a freer flowing exhaust on any of these trucks and with a 600 this only requires a muffler and maybe removing the cat. Installing a TAG is definitely a plus as well.

 

[jjames]

My 600 just turned 1000 miles today. 1st tank of fuel I got 13 mpg hand calculated. Just returned from 400 mile trip today got 17 mpg. That is with the auto, 4x4 and mostly empty. Now my 2001 with 5 spd and 4x4 averaged 17mpg empty and towing my travel trailer it got 13. 5.



I for one am very happy with my new 600. It is an improvement in almost everyway.



I had the Bully Dog air intake system put on at the dealership before I took delivery of the truck, maybe that is why it is doing better than some.

 

[FJfonda]

Just turned 1300 miles. Hand calc I'm at 14 mpg. (My '99 5 sp did 18 mpg on the same commute route on the same winterized fuel. 20 on summer fuel. Hand calc for 140,000 miles). I am waiting for summer fuel and more break in before addressing this with my dealer. Both are driven on secondary roads 30 mi each way 4 or 5 stops and starts and driven like time is money. I need to run some open highway for a full comparison. My '99 actually got worse milage on the open road, but I always attributed that to driving to fast.

With the 600 and auto I was hoping for 16 winter and 18 summer on my commute.

Although I have done nothing to make MPG better, adding the cap does make it worse.

 

[TAdamsCT]

I noticed about 4-5 MPG increase when I put a cap on mine to go back to hunting camp. Thats with a quad, luggage, guns, and 3 people filling the truck!



I was getting around 21-22 mpg on the 500+ mile trip.

 

[rashwor]

Solutions...

my thoughts for what they are worth.



Things you can do:



1) Improve air intake into the engine.

2) Remove / gut cat.

3) Remove / replace muffler with open flow muffler.



Will it truly help? Who knows, but it can't hurt.



Wish list:



1) Cummins to turn off the last injection of the pilot injection system. This is wasted fuel and is done only for emission purposes.

2) A box that will alter the pilot injection pattern so that the last pulse is turned off.



These are the real answers, but the EPA is holding a gun on engine manufatures.

 

[RankRam]

Yep the EPA has Cummins burning more fuel in order to get better emissions.



Sure makes sense to me, thanks EPA.

 

[Ol'TrailDog]

remember a couple of months back, all guys that had just bought a new 555 were all crying and mad at dc because dc didn`t tell them they were coming out with the 600

Yep, I was one of the disgruntled masses. However, it wasn't the 600 question it was the "EGR" fear, uncertainty, and doubt (even see the TDR issues harbinging of the impending doom).



I've dodged the bullet twice, once in 98 when I got "stuck" with a 12v and now getting "stuck" with a 555. Life is good and somebody is watching out for me.

 

[wyosteve]

Well, I may be in the minority, but I'm not complaining. Just hand calc. my first mileage report and come up with 16. 47. My 01 on summer fuel was between 16. 5 and 18 with my driving habits. Only 354 miles on the 600.

 

[klenger]

I like mine too wyosteve. My milage is respectable at between 17 - 18 MPG and the truck is great. I was towing my 10K 5er for a bit yesterday at 75 MPH in 6th gear with power to spare. Had 5 adults in it over the weekend, and the passengers said the room was fine.

 

[ceaman]

Post the good mileages too guys..... so us low mileage guys have an argument

 

[KBennett]

I can only tell you of two ways I improve mileage on my completely stock 305/555. Try to keep the RPM under 2K while cruising and leave the cruise control off on hilly roads. I have a 3. 73 gear and the cruise control will cost me 2 mpg with all the hills and mountains we have here.



My best mileage 18 in town/22 highway. Most of the time I run 14-17 in town/17-20 highway unloaded.



Good luck with getting your problems solved. I think Cummins is on the right track with the 600. They just need to get some of the bugs worked out.

 

[Neibe]

You can't expect to have 325 hp 600 lb/ft of torque and pull 16,000 lbs. down the road at 70 miles an hour and expect to get 15 miles per gallon. Nobody can get that my 97 pulls 10,000 down the road at 75 miles per hour and gets 10 and I'm happy with that.

 

[ceaman]

My 03 did 8,000 pounds at 80 while driving with the cruse set, mountains and no downshifting. Worst mileage I ever got from the 03 was 16mpg.



the 04 wont get 16 on any day... ... best in the 04 is 12mpg

 

[CAgnoli]

Post the good mileages too guys..... so us low mileage guys have an argument



My 2004. 5 3500 QC 4x4 "600" sees 16. 5 to 18 (Hand Calculated) on the open road empty with the cruise set to 65-70. I've got 2234 Miles on the truck right now. (I'm running fuel from a local Indian Reservation, an I put 1/3 bottle of Cetene Boost in with each fillup. )



I did drive the truck 75mph for 110 miles last weekend, and the mileage on the road was 14. 5. I think I was a little "Turbo Happy"



Today, for kicks, I filled up on the Rez (For 1. 49 gallon), and reset the trip computer once I had the truck rolling at 65mpg. The trip computer said 24. 5mpg for a few seconds, then started rolling down slowly, and finally settled at 20. 4. I doubt it's correct. And after driving through the city on my way home, it has since dropped to 16. 8. Over all, I'm happy with my truck, and hope that 19. 5MPG is possible.



I've ordered a new Intake, and a Tonnue Cover, in hopes that I can see that mileage. I'm putting the Tonnue on Friday, so I'll have news on Tuesday after my fillup, to report if the mileage is any better with the box covered.



I've got one question. In several posts lately, I've seen many reply's state "Trust me, you'll know when the motor's broke in"



How in the &*% and I supposed to "Know" when the motor's broke in. I NEVER tow anything, I ALWAYS drive 65-70 on the highway for my 97 mile commute to Amherst, and I can't bring myself to "Drive it like I stole it" (I just paid 41,250 for it..... )



I'm contemplating borrowing a buddy of mine's equipment trailer, and towing my New Holland TC25D4 to work one day, just to say I worked the damn truck.



Again, I'm happy with the rig, I just hope that I can get 19+ empty once the motor's broke in.



As far as "Killin the Cat", I don't have the ambition, nor the spare vacation time for an extended trip to prison. :{



I don't know if this matters, but I just checked my truck build date, and it was built on Feb 4, 2004. Maybe I've got newer code?? A close friend of mine bought one that was built 1/24, and his had the smokey stumbly problem, and was getting very bad mileage. After Ed Shultz of Warren reflashed his truck, the smokey stumblies went away, and the truck is getting an average of 16 with a mix of mostly city driving. (Empty, except for a Diamond Plate toolbox. )

 

[Larv]

Just checked my first tank with almost 500 miles. The tank was one fwy trip of about 75 miles and the rest was driving in a small rural city and rural road. Hand calculated at 17. 0 ... ... . larv