vess33

I have had this truck for about 2 weeks now and am going broke buying diesel. The overhead is showing 10.4 which is high as it came out 8.9 hand calculated. This is all in town driving. It has been cold here but warmer than usual. I know I am using some extra fuel warming up every morning but this seems ridiculous. One thing that I noticed is the warmup time for this truck. I can warm it up for ten minutes, then drive around town, sometimes for a half an hour before it gets to operating temp. If I go into a store for even 5-10 minutes and come back out the temp is allready down to the bottom of the gauge. I replaced the fuel fitler and air filter right off. Have a scheduled appointment for the reflash for mileage. While at the dealer I am going to ask them to look at rail fuel pressure to see if this is part of the problem. I am also going to see about this thing being so cold blooded. thermostat stuck open? could explain lousy mileage?Any thing else to look at? I am new to the 3rd generation trucks. had a 2000 that was mildy bombed and ran great-got good mileage, starting to regret letting it go. Any help would be appreciated.

thanks, nick

underwoodtransp

these new ones cool off really fast. If I don't work mine even on a 40* day it will take half an hour to get warm and only 5 mins will cool it right off.
You would benifit from purchasing the cold front from the dealer it is a vinyl piece that goes infront of the rad. and really helps with the cooling off but doesn't solve it. I don't know what to say about your mileage except you are going to the right place to find out.


Oh yea welcome to the site!!!!!

Foxborough

I am new to Diesels but learned a lot from these guys. I only have 1300 miles on my 2006, 2500. At first I was showing 10-11 mpg on overhead. When I got the chord & winter front, milege now 13 on overhead. The overhead has been running 0.5 mpg lower than hand calc. in city. Went skiing last weekend 17.8 mpg hand calc (15.6 OVH).
I unplug the heater and drive 7 miles to work with (3) of the winter flaps open and the temperature is about 180-190 when I arrive.
I know it is not broke in yet, but not bad for a #7000 truck. My Suburban never got 13 mpg with the same type of driving.

djbikeman

There is also a TSB you can check into for poor fuel mileage on the 04.5. It is a reflash of the computer. If you do a search on this site and others about the TSB, you will find most had very good improvements in mileage. I did.

TSB # 18-037-04

http://dodgeram.info/tsb/2004/18-037-04.htm

I had that done on my 04.5 and it made a difference. As far as warm up goes, the winter front makes a big difference as well. The mopar part # is 82208646. you can buy it for $95-$120 from dealer.

Pipes

Cold start feature is a nice touch for warming up as well. It can be done at the dealer and uses your cruise control buttons as a sort of throttle. I find this feature very handy.

jkitterman

Cut out the long warm up idle. Give it a minute or two and start driving gently. You need a small load to help with the warm-up.

eastmentCTD600

Your mileage is definately below par. I have the same truck with a longbox, live near Denver, CO. my driving is mostly highway, but often stop and go I've never seen my mileage below 14 MPG hand calculated and that was when it was new and not broke in yet. Cold weather which I'll classify as 25 deg. F and below usually knocks off around 2 MPG if it is consistently cool. For reference, my average is typically around 16 - 18 MPG (hand calc) highway miles, and 15-17 MPG stop and go (40 k on the odometer).

What temperatres are you driving in?
How many miles are on the truck?

Suggestions:
Shorter idle times and shut it down when you go into a store.
Buy a winter front as mentioned above
Load the engine more if possible

These, and maybe all, diesels cool down from normal operating temps if left idling. I don't know if you would retain more heat by shutting it down or leaving it idling, however, I'd be inclined to shut it off.

handymantim

Your 8.9 figure is way too low so something isn't right. For reference, I pull a 5-6K trailer around all the time in the city and get between 10 and 11. Without the trailer (which I rarely do) MPG is around 15 with a somewhat heavy foot.

Are you driving around in 4wd (snow)? Are you spinning the tires a lot in the snow? Not trying to point fingers but I used to live in Spokane and know what the winters can be like.

Definitely get the computer flash. It helped my truck. If the flash has already been done, there should be a sticker on the radiator shroud or somewhere nearby.

Like others have said, plugging it in will help the warmup significantly.

ZS

That milage sounds about right to me...

Hey this is not a vehicle designed to drive to the corner store!!

If you're spending 10 mins idling, then only driving around town, you are NOT using your CTD as it was designed so do not expect to get decent milage!

If you want to improve your warm up, well plug it in (I use a timer set to come on a couple hours before I leave for work)...

If you're in a cold climate you can do a search on winter fronts as well...

But in any case, if this is your 'go to the store' vehicle, then don't be looking for the magical 20 MPG....ain't gonna happen!

Put that Cummins to work if you really want to see what it can do!

ZS

Fiftygrit

Hi im up at the bottom end of Alaska, so all winter fuel, 4x2 auto 373 qc 2500, I only have around 1500 miles or so, around town 13.9, town and highway 16.9, and just went for a 2 day highway trip, 22.8 going and 22.9 coming home, on the highway doing around 60 to 70 mph this is all mpg and all done on paper, my overhead said around 18 when i was getting 22 so its way out, i use hawes diesel treat in my fuel about 30ml to every 50 lit. and yes i know metric sucks, but i am very pleased with the power and mpg so far, it can only get better with summer tires and summer fuel, sure hope yours will get better with miles.

vess33

To answer some of your questions.... I have a little over 20,000 miles on the truck. the weather is 25 or below for the most part. We have not had much snow, so most of my driving has been in 2wd. As far as idling is concerned, I do not leave it running while in the store. There have been times when I have been in the store for just a few minutes and come out and the thing has allready cooled off dramaticly. Thanks for the replies on this matter. I am going to start with the reflash and check on a heater cord and cold weather front. I knew this truck would use more fuel than my 2000, but it is using a ton more. My 2000 last winter used nowhere near the fuel and it was alot colder. I think i will have the dealer look at the fuel pressure as well, could be a problem-or I could just be gun shy from my 2000 ram. $2000.00+ on lift and injection pump problems.

thanks, Nick

fredw

might want to look at the latest duramaxes for mileage, should gain at least over 5-7mpg over your cummins with better pulling power tobout

ZS

fredw

SuperGewl

Go back to DC and get yourself a winter cold front. You will be amazed at how much of a difference it will make. It will cut down your warmup time and possibly increase your fuwl mileage due to less time idleing.

ed paul

check tire pressure,,,then get it out on the highyway and beat the hell out of it,,floor it going on the on ramp till u hit 70,,maybe even wind it out in second gear for awhile,,all that idleing and city driving is carboning up the injectors,,i have done it after alot of city driving and it helps,,if i don"t get it out on the highway and brutalize it the mileage just keeps going down,down down