Hello everyone. My name Is Nate and I am from Bristol Tennessee. I have a 2003 2500HD Duramax SB CC 4X4. Just rolled over 40k miles after trip this weekend. Mods are airraid intake, bullydog 4" exhaust -straight piped-with 5"tip, edge hot juice w/ attitude monitor, Amsoil diesel oil w/filter. Made trip empty to Florida with edge set on 1(mileage). Running 70-75mph I got 575 miles out of a tank converting to 23mpg!!!!!!!! I was amazed as I had not really tried to drive for mileage as I am usually on level 5 burning rubber and dumping big clouds of black smoke. On the return trip I was towing a 8k lb. tow behind rv that was 31ft. and got 14 mpg running 70-75mph on level 2 (tow). I am really amazed at the results on fuel mileage especially with diesel over the $2 a gal. I just wanted to introduce myself to everyone and join in on discussion's. This is my 3rd diesel truck I have owned. Future mods are built allison tranny and stack another programmer(don't know which yet) plus whatever I can afford to go faster. Talk to ya soon and hope to get to know everyone soon :ro) Nate

good job nate: and yes those numbers can be had for mileage, i had the same results last summer, and i was running the same speeds as you, and was on summer fuel, since on winter fuel, not as good, i also found the 285 tires had some benifit over the stockers, did not see what your running, we also pull a 33' trailer and have simalar results, i now run with a high stack all the time, and still get very good mileage, makes it easyier on the pocket book at these high fuel price times, good luck with the max

You're sure that your speedo/odo are correct, i.e. have you changed tire sizes and compensated accordingly?

If this is indeed accurate, which I'm not saying it isn't, then I would certainly like your secret. You have obviously pleased the mileage gods with sexual favors, or something of that nature!

Sorry, was not clear on tire size. I have 265/75/16 tires and odo corrected with juice ***. The mileage I run on the tank backs up the figure and we went through several speed limit signs and my speedo was dead nutz on every time at diff. speeds. I guess the better breathing intake & exhaust with edge setting and the synthetic AMSOIL diesel oil and filter have made a awesome fuel mileage combo. I am still amazed and happy with my trip results and glad to hear this is somewhat normal. I love my DMAX more and more every day!!!!!!!!!! :ro)

To my knowledge, the Attitude doesn't actually correct the factory odometer, however. It WILL display the true MPH, but your odometer will still be off according to what I understand.

Just to clarify, I have no personal experience with the Attitude. I'm basing my info on posts by other members and Edge's product info.

Ive managed several tanks of 22 mpg.

But I also did 10 miles of 4x4 on one of those tanks.

Stock tires.

So, yes, if you can keep it between 70 and 75 on the highway, those numbers are inline.

my figures were hand calulated and done with a gps for mileage, did this more than once as well, as you can tell the two trucks that did it are lb7, not lly, from what i read the lly are not as good as the lb7 for mileage, my first box that my great mileage came from was the va smartbox E, on the 110 setting

OK, I'm just trying to become a little more educated here. Trust me, I'm not calling B.S. on anyone, so please don't take it that way. I know that with everything stock on my LLY, cruising for a full tank at 70 will yield right at 17 MPG.

Now that I've got a Predator, I *think* my mileage is up considerably. I just haven't done enough driving with it yet to get some solid data. When I go down to see Mike L. next week, I'll have a good chance to gather some solid info.

I've seen 20 MPG before: stock tires, juice/attitude on level 3/low boost 1, stock intake and stock exhaust (straight piped), shell rotella 15w40 oil, summer fuel. This was with 50% highway and 50% city driving also. I drove it nice for the most part, but hammered on it a few times also. I had 600 miles on the trip odometer and filled up 30 gallons.

I definitely think your numbers are possible, but not normal. I usually average 18 or 19 miles a gallon, but that is driving hard also. I believe I have pretty good mileage because my truck is a reg cab/8ft bed (much less weight). If I cruised 70 all highway miles, I'm sure I could manage 23MPG also... GOOD JOB!!

Dan

Nate .... I believe your numbers.

I caravan every so often with a 2003 LB7 truck. His and mine are near identical, expect for the LLY vs the LB7 engines. Both are running the same stock tires. The LB7 will get 3.5 or more miles per gallon than my LLY. It will beat my LLY by 4.5 mpg on runs with more downhill than uphill. After 200 miles, both odometers are within .10 of a mile. Both are filled at the same station, up to the top of the filler neck. Milage is hand calculated. Most of the miles are run with the cruise controls set to on, traveling on two lane rual highways. My LLY can get just over 20 mpg on these trips cruising at 65, unloaded. The LB7 will get 23.5 or more.

Do I hear about it all the time? Absolutely!

Ok ! If This Is True My Truck Is Broke ! Only Two Times Since I've Had This Truck Its Hit 400 Miles On A Tank And Its Usually Around 350. Can Somebody Tell Me Whats Wrong?

df57,
What are the specs of your truck? model, upgrades, tires, etc?? Everything you do performance wise can affect your truck's mileage, which could offer you good or bad results. Also, if you just bought the truck, depending on where you live, you might be running winter fuel, which lowers fuel economy. On winter fuel, I usually run 16-17MPG, but on summer fuel, I usually run between 18-20MPG. It also depends heavily on your right foot and how you use it! Also, if you have an LLY, it seems that they have lower fuel mileage than the LB7's.
Fuel mileage also depends a lot on where you live and the conditions of where you live. I believe my fuel mileage has a lot to do with the fact that northern Ohio is very flat and I rarely see any hills that would affect fuel mileage.
To sum it up, there are a lot of things that can affect your mileage and not everyone is going to get the same results out of a tank of fuel.

Dan

is it a dually, what mods, is that towing, 350 miles is like 560km, i almost get that towing,

I guess I got screwed again. I have a dully 3500 with hypertech programming. I reset my fuel monitor and drive it mostly highway and interstate 60- 70mph and after 3 tanks full I get 15 mpg. I also have a 6 banger trialblazer that will only squeeze out 19 mpg same conditions. Im gonna be honest and tell you I smell some chit and it aint on my choe.:cool:

WOW--23.5mpg at 70-75mph---that is impressive.

last nite I ran 21.5 at 65 mph...mainly flat freeway from San diego to Los Angeles....but if I go over 65mph..it drops fast.

Method of verification...fill up to filler neck in San Diego....get home..fill up to filler neck. Miles divided by gallons.

I run 265's Revos and have the predator set at 65hp.

I have a 2002 4X4 reg cab ZF and my total average for last year was 21.58 mpg.
Thats with plowing, off road driving, some light towing, etc. In the summer on long highway trips it's not unusual to get 24+ at 68 - 70 mph. I get 21= just driving to work, etc.
My neighbor has a 2001 D/A 2wd reg cab and usually gets 23 - 24.

its hard to compare the 3500 dually to the 2500 single wheel, to differrent vehicles, with different weights, rearends, bodystyle, more wheels, and so on, your mileage sounds normal for a dually, just the nature of the beast):h



I guess I got screwed again. I have a dully 3500 with hypertech programming. I reset my fuel monitor and drive it mostly highway and interstate 60- 70mph and after 3 tanks full I get 15 mpg. I also have a 6 banger trialblazer that will only squeeze out 19 mpg same conditions. Im gonna be honest and tell you I smell some chit and it aint on my choe.:cool:

df57,

fact that northern Ohio is very flat and I rarely see any hills that would affect fuel mileage.

Dan


EH? Northern Ohio flat???? :eek: Oh you must be talking about Western Northern Ohio. I'm up in Northern Ohio and we have plenty of elevation changes here. Ah hell, we even have two ski resorts within three miles of the house.

Sorry about the :rant:

I'm getting ~ 16 - 18, sometimes 20 if I drive West ):h truck has 152,000 miles :ro) just broken in... :exactly:

i can say northwest ohio is flat.....that is where i am from:D

arguy,

I should have clarified that I am located in Northwest/central Ohio... very flat.

Dan

StraitDiesel - very good, I figured it was somewhere West,

thank you

Properly inlfated tires are a very important factor in your fuel mileage.. Make sure none of your tires are under inflated. Under inflated tires rob fuel milage due to the increased resistance rolling down the road.

Thats better than the 14.5 I'm getting right now!!

-:t I wish my duelly would get 17 solo. I never drive it out of level 2 on the attitude. I never trash the truck and drive between 70 and 75 on the hyw. Around town maybe 12.5.

Denny:help:

Just checked my mileage this past weekend. I got 18mpg driving about 65mph. In the summer, I've hit 21mpg. I suspect the winter blend is to blame. I run the 6-gun on level 2.

I was getting around 18 here in Michigan where the weather has been between 10 and 32° thru the winter, respectively. Truck has 63,000 miles. I put the Edge on about 3 weeks ago and am now getting 20 mph to and fro work. Roads are flat two lane paved cornfield roads with a few 4 ways and stop lights. The thing is the Edge doesn’t kick in til the motor is up to temp, so I watch my mpg Drop as I go down the road until I hit 180° (about 15 miles) then she will climb right back up all the way to work. I don’t drive it hard, there is no one to race on my way to work. This is using the DIC and hand calculations, which match up perfect. .I know this summer I can get 23-24 easy.

When I 1st got the truck, I followed a buddy that was towing a big boat up north. I decided to take it easy and she what I could get mpg wise. I filled up before I left and hit 25.5 mpg when we reached our destination. This was really Pu$$y footin’ it though.

03 4x4 juiced on 3-3 intake and 285's not winter blend either. no pulling at all.

Wow I wish I could get that kind of milage. Im in central pa and were still running winter fuel right now, but the last 3 months i have been getting 13 to 15 mph. I know the 285's are not helping. Im not even that hard on the truck usually let it shift gears at 2,000 rpms. I also run stanadyne.

SSNightmare,
Are you adding the percentage of difference between the 245's and 285's for mileage? There was a chart posted on this forum quite a while ago.

Scott,
Yes I am adding hand calculating my milage. The 285's were 7% larger than my 245's so this what I am adding to whatever milage I get out of a tank. Does 13 to15 mph sound low?

With 285's, I would say 15-16mpg on winter fuel is about right. I'm getting 18mpg on 265's, but the Banks 6-Gun gave me an increase of 1.5mpg. On #2 diesel, you should see a 2mpg increase.

i have heard mixed reviews over the 285, but i think it all comes down to the tune your running and if it is lugging the motor to much, for me i seen an increase in mileage, and now the rpm at hiway speeds is about 200rpm lower than the 265 i had, thanks fred




Scott,
Yes I am adding hand calculating my milage. The 285's were 7% larger than my 245's so this what I am adding to whatever milage I get out of a tank. Does 13 to15 mph sound low?

Do you think it would do better if I ran it a little harder, and turned more rpm as not to lug the motor? The truck is stock except for exhaust and air intake no performance mods yet.

if your running 285 on a stock tune, that is your problem for mileage, and i bet every hill your tranny is shifting as well, find yourself a good tune like a powerpup, edge, or va smartbox E and watch your mileage increase if you can keep your foot out of the new found power
http://dieselplace.com/forum/showthread.php?t=25149

I have seen 22mpg in the summer under ideal conditions but not very often. Thats with the edge at level 1 running about 65mph on cruise. Thats also a Canadian gallon so I guess I shouldn't be too happy with that.

Remember that certain types of injector failures your mileage will start to get really good. Mine did the same and the mechanic agreed.

Hey Nate I hate to be the one to say Bull S***. You must average your fuel mileage over at least three tanks of fuel to get a good average. It is my guess that you are getting fooled with foam in the tank, the three tanks will help with more realistic numbers.

I'm seeing 19.7 average (over 5 tanks) traveling 80-85-90 on the highway no load...

Well jman1151 I

Hate to tell ya but I have got these numbers the last 5 tanks or so. My g/f's dad has a 2004 lly dmax and traveled a whole 1,300 mile trip with me to back it up and witness the fuel mileage I was getting. He has ordered everything for his truck that I have on mine now b/c he was convinced after seeing it for himself. I really could not believe it when I was seeing what mileage I was getting either but it is no B.S. That is what my truck gets. If you look through this post you will see several people that have got the same results as me and some even better! --Talk to ya later ------nitrous_nate

I dont pull a trailer but I do carry alot of tools.Running 19.5 to 21.5 mpg.Have a friend with an allison and he cant do better than 18 mpg? Aint nothin flat up here!

Wish I knew the secret - I run straight #2 even in the winter with additives. My commute is 24 miles of highway driving at 65 - 70 mph and I get 17.5 mpg day in day out. The only time I've hit 20 is a weekend in Yellowstone where you never exceed 50 mph!!

There is so much bull$hit in this thread ! There aint noway you run 90 and get 19.7 miles per gallon! If i run 70 i might get 16 to 17 and 85 to 90 i would be lucky to get 14. Seems like some people in here are so blinded by a brand of truck they will say anything to make it sound better. (kinda like the dodge folks)

I can "squeeze" 18.5 - 19 when cruising at 70. At 75 mine dumps off to 16.5 - 17.2. I always calculate mine manually. I have double checked the speedo / juice-attitude with my gps unit and the speedo is still off. That "could" be the reason for the low numbers. I'm running 265's. I've used the gps numbers and calculated and don't really get much better. When the truck was stock (before juice) with stock tires, i got 1.5 - 2 mpg better. I play with it too much.

I think a lot to do with mileage is keeping your foot out of the throttle and watching your gauges. If you put the display on instant mpg and watch your boost gauge you will see what I mean. I have seen fuel mileage be as low as 3 mpg pulling out hard or as much as 30mpg pulling out easy. The same with 4 lane driving. Keep the boost under 10-12lbs. and fuel mileage will stay in the mid 20's - it just feals like your driving like a papaw! If the boost goes much above 12-15 it really starts to suffer. If you mess around with it some watching your gauges and not romping the throttle to pass people or accelerate I think you can improve mileage and see what I mean. Hope this is helpfull, I just wanted to share my expierence's and try to help people get more mileage out of thier trucks with the outrages fuel price of +$2 a gallon. And to all who have said B.S. on me I have witness's that can back it up and traveled with other trucks that filled up when I did and know my results are no B.S. If you are ever around the east tennesse area look me up and we can go on a trip! Later Nitrous_Nate

i agree with doeselfumes57...i'ts impossible ..the faster the worst milage ...the best milage that i have got is cruisin at 65 miles an hour..which i got 22.00 mpg. at 75 it drops to about 19 or 20 mpg..

Just for curiosity sake I drove into town and on the way back I was going 80 mph and reset my fms and was able to get 28 mpg when I got home!! :grd:

2004 LB7 running Amsoil everything elso stock! Extended cab with small box. Made two trips on cruise control set to 70 - result each time; 22.5MPG. Have also taken two trips into the mountains of NH (Boston to N.Conway) and got the same 22.5 MPG much to my surprise since it is a hilly ride. :)
At 80 the milage drops below 20 so I'm always in the slow lane.

There is so much bull$hit in this thread ! There aint noway you run 90 and get 19.7 miles per gallon! If i run 70 i might get 16 to 17 and 85 to 90 i would be lucky to get 14. Seems like some people in here are so blinded by a brand of truck they will say anything to make it sound better. (kinda like the dodge folks)
AAAAMMMMEEEENNNN. Fuel mileage stories are like a$$holes. Everyone that likes to BS has one. Bottom line is, when the tank is empty, you fill it up or resort to tennis shoe transportation (ie walking).