2003 fuel milage

[polaris800]

I have 5000 miles on this truck and currently getting 12/13.5 miles to the gallon. Can someone tell me what they are currently getting on your 03. When will this truck start getting 15/19 mpg?

[hoot]

Winter is a bad time to be too concerned about fuel mileage.

You have a truck that is not broken in running on winter blend, in cold weather, probably some warmup time.

Wait till summer and see how much it improves.

[JJackson]

Polaris800, I have a 2003 w/4,000 miles. During first 500 miles breakin I got 14.5. Then pulled a 13K 5th wheel 3,500 miles... started out getting 8mpg but by the time we got back to Tampa we were getting around 11.5 mpg pulling. Now getting around 17 empty.

John

[Blackwheel]

My 03 has 2800 miles on in now. On the highway, going 70 mph it will average 19 of just under. Thats from three or four trips of over 350 miles each way. In town it gets 14 average. Oh! I have checked the computer milege with what I figure from how much fuel I fill the tank with. The numbers so far have not been more that .2 mpg off.

[GDOG]

I have about 2500 miles on my '03 now. I got about 19 on my only empty highway trip. I recently pulled my 27 foot fifth wheel to the coast on mostly flat terrain with a few hills and got 15.2 pulling. Around town i'm getting about 15 empty. I haven't noticed a drop in mileage due to winter fuel. I'm in Northern California so I don't know if it is the same blend as the colder parts of the country or not as this is the first diesel I've owned. Hope this helps.

[xcpolaris]

My 03 started out at 14-16 mpg at 4000 mi went
to 20.6 on #2 fuel. now on winter blend
put 200 mi on yesterday getting 17.4 .
make a diff where i get fuel cenex seem's to
be best in this area this is running empty
if i pull my skidsteer or 5th travel trailer
get about 14-15


03 chev ext/cab sb d/a lt victory red 4x4
92 6.5 1ton 4x4
02 600xcsp

[ChopperBill]

6000 miles on mine. Just starting to see upper 19's lower 20's cruising at 65-70 empty. In town is hard to say but it is around 13.5 That is with a lot of warm up idling and short to work trips. Going on 2500 mile vacation this fall I got a 1/2 mpg better avarage coming home. Went out on flat Interstate and came home in the Colo mountains. I figure the increase in MPG was because of the increase of miles on the engine.

[Trippin]

I've got about 1100 miles on mine. 13-14 mpg around town. 18-19 mpg on the highway. I'm in Southern Calif. Not sure if we have a winter blend. :D

[naylorseed]

I've got 15,000 mi on my '01 3500 D/A dually. I only average 13-14 mpg empty daily hiway driving. My juiced '93 Dodge dually gets 17 mpg. I've had the dealer do available updates as of Nov.'02. I love the truck, but everyone else seems to get better mileage.

[FirstDiesel]

Not everyone.

I'm stock except for the airfilter. Best mileage I seem to average is 14-15. I ONCE got 18 on the highway but it's usually 15. I'm a little puzzled looking at all the claims of 18,20,22 MPG thrown around here at times. I don't have a lead foot in the truck since if I want to go fast I drive my sportscars.

[smitty8401]

Just today I traveled from Upstate NY to Kingston Canada. I got 18-19 miles per gallon empty. I have an 02 GMC 2500 HD Crew Cab DD/Allison with 5000 miles on it. Good Luck, hope it gets better for you.

[trout49]

I have GMC 3500, and I didn't buy the truck for the mileage. I bought it to tow. It is my daily driver and I get 13-14 MPG if I keep it under 55 MPH. I drive 15 miles to work on the highway with an additional 2-3 miles stop and go in town. If I try to drive 60 or over mileage drops to 12-13 MPG.
Like I said I bought it to tow. I think all the folks getting 18-20 are the 2500 crowd. And they should get better MPG. A 3/4 ton shortbed is lighter than a 3500 longbed. I'm still getting 2MPG better than my 99 6.0 shortbed that I traded for this truck so I'm not unhappy.
I have 7600 trouble free "stock" miles.

[FirstDiesel]

trout49

Your right. I bought mine to tow also. I understand I've got the 3500 and won't get the mileage that some of the others get. I'm just wondering how these people are getting 20+ mpg. :confused:

BTW, I bought mine to replace a gas Subbie that only got me 12-13 MPG without a trailer. So I'm ahead of the game at 15. And the Subbie towed a small open trailer and got 8-10. I get 12-14 towing a 32' enclosed trailer now. :D

[Tsckey]

I don't keep meticulous records, but I check the mileage at every tank. I'm averaging around 16.3. On the highway at 80 I get just under 17. At more reasonable speeds, 75 and under, high 18s and low 19s are normal. Recently, on my way back from Colorado, I averaged 20.34 between Colorado Springs and Grand Junction. That's 273 miles, including 11+ thousand foot Hoosier Pass and a couple others I don't remember. That one surprised me. I guess the engine really doesn't have to work all that hard on the climbs and the speeds on the open sections generally were moderate, 65 - 70. Anyway, very good mileage from a terrific truck, EGR, catalyst and all.

TC

[rrocket]

Has anybody noticed any effect on the trucks onboard milage computer when "Juiced"?

I have 9200 miles on my 03, put the juice on about 5k.
Previous got about 19.5mpg from NH to Canada
70/75 computer seemed to agree with fuel used.
Juiced the beast, and towed a 7600# trailer from NH to FL.
Computer say's 15.7 mpg average over 1400 miles
Fuel used say's about 13.7 again 70/75mph
Used the juice in level #1 T/H mode with Amsoil air filter.
Using Amsoil synthetic oil,and JK's fuel additive.
All else is stock.(haven't gotten around to installing the SPP, and headlight harness yet.)
Had to remind myself I "HAD" a trailer behind me!!
Has anyone else seen any great desparities from the computer ? with or without Juice?
Thanks, and this truck just keeps growing on ya!
Thanks Paul

[Seattle Steve]

I'm at 495 miles now and still on the first tank of fuel. The truck is bone stock and the computer says 21.3 with combination city and 65MPH highway (60MPH speedlimit) driving. When I fill it up again later this week, I'll check actual mileage versus the computer and post what I learn. I have had my foot in it here and there, but not often due to break-in.

Note the manual trans in my sig. The allison works the engine much harder (higher revs) than I do based on my test drives of the D/A. I'm sure the higher rpm shift points are great for when loaded, however this engine has so much power, it sure doesn't need that when empty. That is why I ordered the ZF6 and I'm very happy with it so far.

[NoMo]

polaris800-
Could your poor mileage be a result of the [over]cooling problems you are having? It's my understanding that diesels need to be "hot" for them to be efficient.

That being said, running empty, my little 2500 short-bed 4x2 has never gotten worse than 17.3 MPG on a tank. I drive about 60% highway at 70-75mph and 40% stoplight drags in town.

[ski]

I have an 03 CC SB and get around 15.5 in town and upwards of 18 - 19 on the highway. Southern NM, pump still says #2 (does not get real cold very often)

[10851]

Polaris800 I have an 03 2500 with 3.73, 4X4, Allison. I only got 14-16 when I had less than 4K on the truck. If I drive around 70 mph on flat highway I can get 19 mpg. If I run around 60 on the same stretch of highway I have gotten up to 21.4. Are you doing the math yourself, or are you using the DIC? Do you have 4.10 gears? Check the air pressure in your tires. Is someone stealing your fuel? Do you have good power? Is the transmission shifting into 5th gear? Could be alot of things..start with the easy ones first. Good luck!

[ 01-06-2003: Message edited by: 10851 ]</p>

[4x4man]

I have almost 800 miles on my '03 and I am getting a tad over 15mpg with combo highway and city driving. I still have about 3/4 tank of fuel and the DIC is showing 15.5 average. It has been pretty accurate on the first two tanks. Mileage is MUCH better than the '01 8.1/Alli I traded in!! :D

Bob

[Runaway]

I have an "03" 2500 D/A combo. Best mileage to date has been 21.1 running 55 - 60 mph. Worst mileage was last week running 75 mph from Lincoln Ne to Cheyenne, Wy against a VERY heavy westerly wind in the neighborhood of 35 - 40 mph. Truck got 15 mpg on the nose. The total trip I put on 2600 miles, DIC said 17.7 mpg for the trip average, when figured by hand I came up with 17.3. I feel this computer is darn accurate.

Polaris, you posted a heating problem before Christmas, is that problem resolved now? This may cause part of the problem, but you being a previous diesel owner, I'm preaching to the choir.

I found on my truck on its first servicing that all but two of my intercooler hoses were loose. This can/could cause performance/mileage problems.

Fuel filter I feel needs to be changed within first 1500 - 3000 miles as there is residue in fuel tanks that can gum up the filter (found this out a previous truck the hard way).

ALSO: A 3500 compared to 2500 is comparing apples to pears. The 3500's don't get the same mileage empty as the 2500's do.

Just my two pennies worth here.

[ct0218]

I do a lot of towing, and I just returned from a 900 mile trip to NC. 4200 miles on the odo, 16.0 running 65-70 most of the time, and solo. Guess thats not too bad for 8200 lbs (weighed on FL DOT scales)

[Grizz272]

I am on my third tank of Diesel. First tank was 17.3 mpg driving at different speeds. Second tank was 17.4 mpg again varing the speed. Tommorrow I am taking my Daughter up to school so the truck is loaded down some what. I intend to drive it like I stole and see what happens. Already I am getting bettr winter mileage than my old f@$d. I even like the winter cover on the grill :D

Grizz
2K3 EC SB 4x4 D/A

[FisHn2DMax]

On a recent family holiday 750 mile round trip from Northern,Utah to South Eastern,Nevada and back, My 03 4x4 CC D/A averaged 18.2 mpg (using winter blended fuel) going down and return trip was 17.8 mpg( non-winter). 80-85 MPH most of the way, unless laser detector was screaming, then down to 75 mph for a few miles. If I could just stay at 65 mph or less (yea right), I know this truck could get around 20 MPG.

:eek:

[Grizz272]

300 miles round trip to take My Daughter back to college.(still less than 1000 miles on her) Going up clear weather dry roads 75-80 mph (I told my WIFE that the cruise was set at 70mph all the way). With the winter cover on I got 18 mpg. Coming back at night snowing in 4wd @ 40-45 mph I got 17.5 mpg. This truck is great!! I went out and did some donuts today to see how she spins and slides. Man was that FUN!!!!!!! And you guys says it only gets better I can't wait!!! :D

[FirstDiesel]

Wow less than 1000 miles on her and she's in college??? smile.gif

I love my 3500 and it's what I need for my towing but I hate you guys that are getting 18-20 MPG. I seem to average around 15. Then again I replace a gas Suburban that never got better than 13 and certainly wouldn't tow this new trailer.

[ 01-05-2003: Message edited by: FirstDiesel ]</p>

[Seattle Steve]

Here's some info on my first fill-ups.

1st time I ran it to "E" and the DIC said 28 gallons used (34 gal tank), fuel pump said 30.0 when I filled the tank. DIC said 20.6 MPG, calculated out to 19.2. Combination driving with 65 MPH on 60MPH freeways. Note the 4 gallon reserve which is great to help avoid priming if it runs empty.

2nd time I filled it when the gauge said 1/2. The DIC said 17.3 gals used and the pump said 17.375. 18.9 MPG mostly 75MPH on the highway driving over a mountain pass (3000' elev change).

3rd time was just for resetting things at the end of a trip. DIC said 8 gals used, pump said 8.6. DIC said 20.9 MPG, I calculated 19.5. Mostly 75MPH highway driving coming back over the pass.

By the way, the speedo is about 1% fast which takes a little less than two tenths off the #'s posted above. I was running Stanadyne additive on the 2nd and 3rd fillups. I let the foam settle a little each time to "top off" the tank and I'm sure that and truck leveling has an influence on accuracy of the DIC versus the pump. I will post again if I learn more about factors to "dial in" the accuracy.

I am very pleased to average 19 MPG with this truck!!