I am new too this game so please be kind :o:. I have had an 04 3500 Dullay 4x4 Crew cab for about 5 months now. Empty not towing driving with light foot cant seem to break 15mpg. If this is normal I am cool with that,love the truck .just thought I would ask

I have an '02 the best I used to get was 11.5, 9.5 loaded. After dieselkleen I have seen 14.5 best usually 13.5. Haven't towed yet so don't know the loaded mileage.

My 05 is typ 13-14 empty and the worst towing was 5.9 the best 8.9, notes that @ 72 mph and pulling 24-25k.
Marty

I have an 02 and average 14-17 empty W/Edge level "3", 10 with 14K load. Always hand figured at every fill. Not bad for here in the hills. Had gotten as high as 19 before the Edge w/Attitude but I'll sacrifice mileage for the extra torque it provides and never look back. Still beats the 2000 454 I had before 12 and 7 mpg.

Are your mileage figures combined city/open road driving, or what? What speed do you drive? Mine varies a lot--11-12 stop and go around town, 18 or slightly better interstate at the speed limit. Above 70 it drops fast.

example just drove to Ohio from St louis set cruise at 65 outside temp was aprox 75 drove non stop 14.9 mpg hand figured. If thats normal thats fine dont have any mods yet and though it would be just a tad beter. LOVE TO DRIVE THIS TRUCK

example just drove to Ohio from St louis set cruise at 65 outside temp was aprox 75 drove non stop 14.9 mpg hand figured. If thats normal thats fine dont have any mods yet and though it would be just a tad beter. LOVE TO DRIVE THIS TRUCK I just made a trip from Ohio to Missouri with about the exact same conditions and got about that exact same mileage. I too was hoping for a bit better but that is about right.

Are your mileage figures combined city/open road driving, or what? What speed do you drive? Mine varies a lot--11-12 stop and go around town, 18 or slightly better interstate at the speed limit. Above 70 it drops fast.

I was getting about 15 MPG overall driving conditions which is a combination of highway and city. Since making my mod's, I have boosted it to almost 19 MPG.

But I have found the biggest thing to fuel mileage on the highway is to keep the RPM's below 2200. When I keep the RPM's at or near 2000, I get about 2 additional MPG. So the biggest determination when it comes to getting mileageout of a tank of fuel, is how fast do you want to get there. IMHO anyway...

Lately I've been getting 15-16, hand calculated, using JJ's DP filling technique, on a mix of around town/ highway driving. This has improved about 1 mpg since we have changed from winter blend. I've got 12K on the truck. Road mpg is about 1 mpg better. Seem to get best miliage using Shell fuel, which also seems to cost the most around here.

warrior, the posts above are correct based upon what I've read elsewhere and my experience with my 02 Duramax.

Now, if you've got an 8.1, then give yourself a pat on the back as you're doing great and will never see anything over 15. The best I've gotten this summer unloaded was 14 mpg and that's driving at 52 mph with no passing...

I have an 02 2500HD 2 WD CC and have ordered a 05 3500 DW 4 WD CC. I was wondering a bout the differnce in milage. I get 17.2 to 17.8 on Interstate runing 70/75. with 265 tires was doing better with stock tires. Do you think there is much difference in the 4 WD and 2 WD in the Dually.

I have an 02 and average 14-17 empty W/Edge level "3", 10 with 14K load. Always hand figured at every fill. Not bad for here in the hills. Had gotten as high as 19 before the Edge w/Attitude but I'll sacrifice mileage for the extra torque it provides and never look back. Still beats the 2000 454 I had before 12 and 7 mpg.

:exactly: I had a '93 454 that thing got 10 empty 5 loaded-:t and it rode like a lumber wagon. I still have it as a ranch truck, 1 new engine, 1 new transmission, 1 new rear end. 220k miles showing, more like 250k with the bigger tires.

Thanks for the info Guys. Sounds like every thing is OK so I will leave it at that. I cant wait to start with the mods , I have put nice wheels and larger tires on they look great on the dullay. This sight has been great

our '02 has over 88,000 miles on it ... hand calculate mileage every tank and have a log in which it is recorded ... empty, driving to get good mileage to work and back which is 60% country driving, fairly level roads at 55 mph with Hot Juice set on 90 hp she'll consistently get 17 to 17.5 ... without Juice around 15 ... last summer 10,095 miles trying to keep her around 2,000 rpm, towing 10,000-11,000 pound camper averaged 12.5, would estimate 80-90% towing and rest sight seeing running empty ... speed has consistently proven to be the major enemy of mileage for our truck ... the more you go past 2,000 rpm, the faster the mileage drops

Jim

Yes I have noticed that speed and rpm on highway have alot to do with MPG. I was used too my 1/2 ton Chevy w/5.7 that truck got 15mpg no mater what 80mph or 55. I do try to set cruise at 65, kick back, and let the truck eat up the highway one mile at a time. However sometimes my evil twin is at the wheel and he likes speed. You know how that can be.

I went from Wi to las wages (I80/I15) emty.... best mpg was 19.2. coming back (I40/I55) pulled a 26' prowler 5th (late 80's model) and got 14.8. during the winter I get 13.8 to 14.4. in the summer when we go back to the #1 fuel I can usually get around 16.4, I just put 235/85 on and my rpm's run 2100 @ 72 mph(dont want the bears chasing me), this should help my mpg some, anything over the ol man's '76 Heavy3/4 burb 4x 454 (11 loaded or emty) is fine with me.

I am finally getting good milege with the new LLY. Just got back from WI last night and got 10.9 loaded and 13.7 empty. The truck and trailer weighs 14800# empty so I was pretty happy. Loaded weight was 26,300#.

04 LB7,117,000 MI. combined city/highway avg. 17 mpg. been that way since new.

My 05, with 4000 miles is now getting about 15-16 highway and about 14 combined city and highway. Towing 15k 5th wheel worst was 8.62 and best was 10.5. Dually's are not going to get the mileage a SRW 2500HD will, and the LLY's, overall, do not seem to do as well as the LB7's.

as an idea that i have seen giving me a noticable mileage increase with better tq while towing has been the addition of lp, with our 9k trailer i have seen on the dic an increase of 2.5mpg when lp is turned on compared to not, and a instant feeling of the extra tq, very simple to install, and i have been seeing 500 plus miles out of a 7.9 gallon tank, fits nicely in the tool box

Got my best mileage when I brought it home from the dealer when I bought it, and during the rest of the break in period, doing 55-60 on the highway. 18 mpg

Since then it's about 17 mpg doing 65-70

Mostly around town driving it's about 13.5 mpg
In the winter it drop's to about 12 mpg

I avg.18 to 19 empty & 10 to 12 depending on size of trailer I am delivering. I cruise it around 65-68mph, anything faster & the mileage suffers greatly.

Understand that the CC 3500 Dually weighs over 1500lb more than a regular cab 2500HD. That and the increased wind resistance and extra rolling resistance from the dual tires keeps the mileage much lower than the 2500HD's.

You need to compare your mileage to gasoline duallies to see why the diesel is superior. Few get over 10mpg hwy.

I'm happy :) 15~16 city almost 20 highway, drops to 14 pull'n the boat, 12 pull'n the camper if I stay away from the hills. My Ford f250 with the big 7.5 ltr would get 10 running mt and 5 towing. Even with the big tanks and exhaust and intake mods the thing would only go 500 miles on 53 gallons of fuel! I think it had a 1/2" fuel line. Damn thing would not get out of it's own way! -:t I think it had 220 hp - POS!!!!!

I have an 05 LLY dually with around 7500 and have been consistently getting same averages as others. Around 14.5 combined city/hwy and 15.5 to 16 highway. When towing my 14k boat and trailer the mileage is around 11. I too notice a difference in mileage when I get above 2000 rpms or about 65mph.

Just got back from a 1700 mile trip. I tipped the scales at 16,420 lbs on the way out of town with the camper on and the boat attached. I hand calculated milage at each fill up. My best was 11.6mpg on a narrow highway no passing going 60-65. Worst was 9.5 on 101 South from Paso Robles, Ca. 70 with short bursts to 75. When my truck was new I was getting 14.5mpg empty freeway moderate traffic. Now I get 17 on the same drive...I have to agree that the best milage is under 2000 rpm........Cal

96 K3500: 15-16 around town, A little better on highway...

Did get close to 20mpg on a Florida round trip,

3000 lb Truck camper: 12-13 Avarge over 3500 miles ( mixed interstate & PA back roads ) Check milage several times on same trip, not much variance..

Have gotten close to 15 with the camper at 50-55 on flat ground...

i have a 98 6.5 dually. i get 17.28 miles per gallon. mind you we in canada have a larger gallon than u. not sure how much the conversion is. this is also loaded with a 9.5 ft. kodiak camper. just my 2 cents ed

averageing over 17 in town out of town mix unloaded, with heavy @$$ bumpers and a heavy toolbox. the factory sized tires don't seem to hurt though that is with out diesel kleen. with diesel kleen it usually does better but not always

Before I started using the "proposed" DP MPG Calculation Method IIRC I posted a high of 16-17mpg city, 23mpg highway at 60mph. Now that I am filling my tank consistently I usually get between 14-15mpg around town, 17-19mpg on the highway.

Not bad for big ol' bubble butt truck! JJ :)

This is in response to the fuel mileage woes being posted.

Notice the signature what I am running. Add a 5th wheel box and hitch and goose neck hitch and full of fuel. I am running with no trailer about 8500 lbs. In town, whenever that is, I average 15-16 mpg. Unloaded on highway driving 75-77 mph I get aver 16.5-17.5 mpg. Depending on the tow load weight and what it is and where I am towing it to and how fast I drive I will get from 7.5 to 13.5 mpg. If I stay aroung 2000 -2100 rpm I will get the best which averages 10-11 mpg towing. I find these acceptable numbers for a truck as heavy in weight and power as this truck is. It takes fuel to make power and lots of it.

If you want real good mileage with a diesel buy a VW or some other such tuna can.

Tom Cobb

yeah, what he said..... big trucks, big loads, big fuel bills!

First tank, exactly 499.9 miles on the tripometer, no fuel light yet, but hovering close to the "E". Took 29.997 gallons to fill it = 16.6 mpg (town and some freeway driving) hand calc. Not bad considering I was only getting 12 mpg with my 6.0 v8 2500HD.

I am still hangin right on mark with 15-16mpg unloaded and 11-12mpg towing various trailers and weight. But I can say this, lugging weight over mountains is really fuel consuming. Flat land towing is much better for MPG.

About 90% of my driving is from 'farm to market' 55 miles, all highway at 55 or more. I keep it between 64 and 70 and have averaged over 17 mpg on the last three tanks. That's hand figured, not DIC's version. Truck is "full-bodied" ):h and has 48,000 on it now. I recall nearing 20 mpg through Montana last year while on vacation. I've also been told by several locals that Shell/Texaco diesel gives more MPGs.... but it does cost more.

Oh yeah, I'm runniing a 'Tonneau Master' on, which I feel is good for almost 1 mpg.... Just a guess, no scientific evidence.

Klvn8r,
I have had 2 occasions of 19+ mpg. Both were similar to your findings. 55-60 mpg, cruise on. It takes discipline for sure. I just cannot do it.. I have tried. 55 is just way to slow. Feel like I am holding up traffic. so 70+ it is and 15-16 mpg.

The 05 has over 11,000 miles on it and is driven at 4.5K to 6K mountainous terrain. Town has 6 stoplites and is 15 miles away.

Running lite, combined fuel use is 14-16 mpg. Highballing the Interstate at 15-17 MPG.

Loaded and pulling 8K travel trailer getting 12-13 MPG average.

Considering the power this truck has and its weight of near 7500 lbs, the MPG's are outstanding!

Note: When Spousal Unit is driving, cut MPG by at least 1/3! She has to burn rubber to and from the Wal-Mart and yard sales! She loves that truck!;)

Note: When Spousal Unit is driving, cut MPG by at least 1/3! She has to burn rubber to and from the Wal-Mart and yard sales! She loves that truck!;)
:funnypost :muahaha:

05. dodge 3500 dually diesel quad cab auto 373. 12.9 empty and babying it, 9.1 towing about 13000 lbs. im not so happy.

Our 04 SLT CC 4x6 gets about 21 MPG at 70 MPH on highway empty and 13.5 MPG pulling our 14K 37' 5er.

Added a K&N standard filter, Edge EZ module on Level 1 always and MBRP exhaust. Also use Diesel Kleene.

Man That's Great. Did The Extras Help That Much Or Was It That Good Stock

On my 2004.5 LLY I was seeing about 17 mpg according to the DIC on my drive to and from work. While the truck was in the shop the other day, had the reflash done and now I'm see 14.5 mpg according to the DIC in the same driving conditions.:mad: :wtf:

I just thought I was below avg., until I read the avgs. here. The best I ever got was 19.5 mpg doing 65 mph on the interstate. Normal is 16.5 to 17 mpg empty driving 72-75 mph. Loaded betweens on the weight. Total weight of truck/trailer/load @12-16K is about 11-12 mpg. Total weight @26-28K is about 9-10 mpg. When I get above 30K it drops to about 8 mpg. If on the interstate pulling a load, I am usually running 75-85 mph in order to keep it in the higher RPM, especially in hills.

I just made a run to Logan, UT with a 7,000 horse trailer and was running 70-75 mph and got 12.5 mpg. Was very surprised. I came back empty, (8500 lbs) drove 80 mph most of the way when I could and got 16 mpg. I made a similar run without the a/c on a few months back but run at 75-77 mph and got 17.4.

With the 41 gal aux and 34 gal main tank I fueled up in Wamsutter, Wy and drove to Hurst, TX (next to Ft. Worth) 1045 miles without fueling up. I did have to make a few pit stops though to let the iced tea out.

Tom Cobb

I have an 04 crew dually 4x4 long bed LLY allison, 4.10s. With 2000 miles on it a round trip to FL and back and a 500 lb load...............13.09 mpg round trip average. Speed 70-75
Now with 10K miles 2500 mile round trip 2 weeks ago..........worst 16mpg, best 17.3, this trip had 1000lbs in bed.............speed on hiway 70 -75

All tanks of fuel filled to top of neck, all tanks hand checked............mileage vs gals used.

Truck BONE stock

I have an 04 crew dually 4x4 long bed LLY allison, 4.10s.............Truck BONE stock

4.10?? Is that the rearend ratio? If so, they must have changed things. I know when I bought my '02 the ONLY rearend available was the 3.73?:confused:

my 04.5 has never seen above 15.5 and that is going by the DIC. I drive 40 miles a day to work and back, mostly open road with cruise set on 65. I average around 14.5.

15.7 about the best I can get highway. Still better than powerstrokeby 5 mpg all else equal.

I have an LB7 w/373's and an Edge Chip that honestly gets 19-21mpg!

4.10?? Is that the rearend ratio? If so, they must have changed things. I know when I bought my '02 the ONLY rearend available was the 3.73?:confused:

Has anyone answered this question yet? :confused: :offtopic:

Has anyone answered this question yet? :confused:

I think someone is just confused.

I think someone is just confused.

Yup.... :offtopic:

But to get to the theme of this string..... :exactly:
My 3500, 4x4 D/A :
got 13 mpg with a big Lance camper.
got 11 mpg with a 22' Weekend Warrior Toyhauler Trailer loaded
gets 9 mpg with a 33" Weekend Warrior Toyhauler 5th wheel loaded

Got 19 once but it was down hill all the way from Denver to Okie City with a tail wind, normaly 15 empty, an 12 with camper on an pullin the boat if I stay under 70. The faster I go the milage goes with it have got as low as 8 loaded.

Anyone know where I can get a down pipe 4"

I just did a 5300 mile round trip to New York and got about 15mpg.
I have an 05 CC LB Duelly and it has 3.73 gears

I have an 02 with 4" exhaust, and PPE 1000CFM air intake. I get about 16.6 combined. Mostly round town. With the trailer (32' 5th) it loads out at about 21k and I get in the 9-11 range depending on hills.

I just did a San Diego, CA to Tuscon, AZ and back this weekend. 650 lbs worth of people & 500 LBS of stuff in the bed with the tonneau cover on. I had the Edge set on 1x1. Cruised at 65-70 going over and got 18.1 mpg hand calculated. Cruised back at 70-75 and got 17.3 mpg hand calculated. The temperature ranged from 105 to 113. The tranny temp stayed below 190 F. and the engine temp never got above 205 F. The AC worked great and spit ice cubes at us even when in town traffic or idling at 113 F. I am very impressed as it only had 2900 miles on the odometer at the start of the trip. This is my first diesel. Around town I have been getting 12.5-14 mpg. I am one of the guys that said I will never ever own one of those noisy slow pieces of you know what. Diesel is priced at about 3.15 per gallon here in CA. and in AZ we paid 2.75 per gallon.
Welcome to California, NOW PAY THROUGH THE NOSE.
Fuel must be cheaper in AZ beacuse they have to haul it farther..............Jack

Dually's are not going to get the mileage a SRW 2500HD will, and the LLY's, overall, do not seem to do as well as the LB7's.
That is a fact! My 01 Crew Cab dually got 18 mpg empty on the hwy at 70 mph, 16 city / hwy empty and 12mpg at 70 pulling 12500 pounds of RV.

My 05 Crew Cab dually gets 14 on the hwy at 70mph, 15 city /hwy and 9.5 pulling only a measly 4000 pounds.:(

I just towed my 5th wheel from Placerville, Ca to Mammath via hwy395. With the bikes, 1 quad, and 100 gallons of water I probably was towing a good 12,000 lbs. I got 9 mpg on the way there and ~14 on the way back. (going from 2,000 feet to 8,100 feet. )

hello warrior, I have a 2005 duramax with 7500 miles and the fuel mileage is at 17 on the highway and I tow a 13,500 pound fifth wheel and getting 9.5 miles to the gallon and this is re-setting the computer when I fuel up or start towing, I am told that around 10,000 miles it will really start to improve. good luck on your new truck.

Just got my Duramax in June. 2005 Long bed, crew cab, dually. Drove from SF Bay Area to Son's house in Colfax, CA with 400 miles on the OD. Got 18.1 empty. Speeds varied from 50 to 80 for break-in. Last month took a trip on I-80 over to Fallon, NV, then back over Sonora Pass on 108. Got 18 first tank, 17.5 second tank. Last week with 4K OD miles, hooked up 32' travel trailer (9,000 lbs) and went up I-50 to Lake Tahoe. Got 12.5 on the way up and 13.5 on the way back. All mileage hand calculated. Real happy with this one. My two other Cummins powered rigs (both with 4.11 rear ends) will be lucky to see 17.5 at a steady 60mph, but do get 12 towing.

Towing a 24 Box Trailer M/T 12.8 MPG
With 150 Bales of Hay 9.5 MPG