I'm just curious. I've tried many different things that are supposed to improve fuel economy. Most are just a bunch of junk or snake oil. I currently get an honest, calculated by hand, 18.2 mpg overall with about 60-70% of my driving on the highway. Changes are a 4" exhaust, coolmyduramax CAI, and my larger-than-stock 285/70R17 A/T tires on H2 wheels. Front torsion bars are cranked about 1.5".

So what are you really getting?

Sounds damn good to me, I couldnt get over 15 highway with a 285 on.

I am averaging around 17 in town and unloaded (when I can keep my foot out of it). Drops down to 14 when loaded (feed, tractor, misc junk). I would probably do better if I could keep my foot out of it when leaving stop lights. Mine is essentially stock except for the 285/16 Nittos. 18 mpg sound good.

Mines not great in town because of the 37's, but on the highway, i can push 18/19 easily.

Truck and mods in sig. Local driving about 14-15mpg since its warmed up, it was 11-12 all winter. Best I have got was 19mpg all interstate. Oh and a worst of around 7.5mpg- this was grossing about 23k running about 70 on the interstate.

I get about 16-17 with a combo of driving. I have gotten 21.2 hand calculated on one tank 100% interstate. My Hwy avg. is normally about 19-19.5 .

mine is getting 15 city and will go up to 16 when it warms up and 20 to 21 on highway unloaded. with tuner on tow econ. scared to try the 135 setting keep hearing that it would give me the best milage but i dont want to hurt tranny.:cool::cool:

My dic says my average overall is 11.5. That includes towing, idling, etc. My best tank I have ever had on the freeway at 80 mph is 15.8 hand calculated.

I get a honest 15.5-16 in mix 60/40. On the freeway it depends on my speed, under 65 I can get about 19, 70=17 and 75=15. The best EVER tank I got was when I was on a trip to Houston with a 20+ tail wind driving 70 I got 21.2.

Kevin

hand calc with ACCURATE speedo. 13mpg around town,15 mpg highway if i keep it around 65mph .Slower maybe 16mpg but I cant drive 55!!!!!! I love my big bottomed girl

Hard for me to answer that question....I get around 15 in the city and 23+ on the highway. My truck seems to like going 70+MPH

I reported above 20, 'cause that's what I do the most of these days. It breaks down as follows:

16.5-18 in town/mixed (my commute is as much highway as it is in town)
Just under 22 on the highway (not towing) - best ever was 22.4
11-14 towing our 24' TTI've got the dates and details in a log book if anyone doesn't believe me. I'm hoping for 25 by this summer. FWIW, I've been talking with a PowerJoke owner up in Indiana who's been making various aero mods to a 3500 non-dually who's approaching 30 mpg. It can be done if you're willing to change some things.

I can get about 17 on the highway unloaded running about 70 with my race tunes.

Mostly in town driving, with 265/75r 16's. Looking for ways to get better as well.

16-17 hwy......14 around town

I don't hand calculate all that often, mostly because I didn't buy my truck for fuel milage, but I get around 14-15 in town. Best I've ever done is 17.1, but my trucks at full weight, tool, ect. all the time with 285's on H2's as well. I would always like to improve milage, but all in all, i'm happy with what I get.

With my 3500 4x4 stock with about 30,000 miles on it so far, I average 17.5 US Mpg = 13.5 litres/100km ( I calced every tankful since new) around here pretty consistently driving empty, mostly 50 -100 mile trips on the highway, some local driving, a few trips up to the ski-hill.

This would be running at 100-115 kmh = 65-75 mph

If I make a longer trip on the highway, I have gotten as good as 18.8 = 12.5 l/100km for a tankfull.

On a number of Camping trips as shown at left, I'll get around 13 mpg = 18 l/100km

Really!

Mine depends also...

-17-19 average unloaded
-as good as 21.9 on Hwy at 75mph
-just got 10.4 this weekend towing a 30' toyhauler at all posted speed limits:mad:

Freeway @ 2000 RPM = 20 MPG doing 65 MPH (unloaded)

Towing my racecar is more like 16 MPG @ 65 MPH

I drive the same trip up and down I-95 a couple times a month, each trip I get passed by the same cars over and over, I guess they drive faster, but they stop more frequently, while I just keep chugging along at 65 MPH, good thing is I dont have to worry about getting a speeding ticket at 65, I'm the slowest one out there.

I get 16-17 in town and 18-20 on the highway. My truck likes 65mph and over 80 mph but in between there it suffers on the highway. Still better than a gas truck in sooooo many ways.

2005 Crew Cab 2500HD LLY w/ 265 Nitto's - Everything else stock

Town-15-16. Then goin a 100 miles stretch at 60 mph i got a 21.2MPG hand calc. Best i have ever got.

My last two calculations came to 23.4 and 23.1 both on windy days and bad traffic where I sat for an extra 20 min (the lower number) 80% of the trips are at 65mph the rest is 40-50 with stoplights covering around 180 miles total.

Truck is an '05 2500HD Dmax extended cab/shortbed weighing approx 8100lbs loaded (weighed on scale). Has a 4" turbo back exhaust, K&N air filter, soft bed cover(until next week) lowered 2" and has factory front air dam and tow mirrors. I just removed the front axles last weekend and that gave me an immediate 1.5 mpg. Mind you the front axles hold the hubs together so I replaced with 1 1/4" bolts . . . I mainly did this because I have the front axle seal leak with the haf shaft that doesnt want to come out . . . I'll repair it later but I have a 4000 mile trip to make in a couple weeks, dont have time to mess with it and would rather not sling oil all over the place.

Oh, tires at 70psi, needs an alignment (pulls to the left w/new tires)

Trying hypertech at stage one tomorrow for the first time, and this weekend building a new sloped fiberglass bed cover, eventually looking to make stainless under panels . . . I have the stainless not the time.

Tried the EGR thing (unplugging it) and I think MPG got worse. I drive up to 1000 miles a week and sometimes more so I'm trying many different combinations. Shooting for 26+ for real :) mostly looking for range since I don't pay for my fuel.

Last time I did an honest calculation I was getting 17-18 mpg on the freeway, but that was doing about 75 mph. Around town, I am getting somwhere around 14 mpg.

My overall is 15. On the highway I usually get 17-19 and around town I get 13-15.
Mileage Sheet (http://spreadsheets.google.com/pub?key=pfK1rhg6Fre-grPfB9ByMIA)

x2

15-16mpg here.

My Milage Was 20 Mpg. Before Propane. Just Insalled Proane Sofar Gained About 3-4 Mpg. TRY ALSO SWITCHING TO SYNTHETIC OIL.

Best tank I ever had was when I was bone stock going 60 mph on the freeway...I had gotten 23 mpg...I was floored. Now with 285's I can't seem to get any higher than 19-19.5 mpg...Oh well, truck looks better.

i dont kno what happend to my mpg's,i was getting the 19-24 mpg when it was new.now its only getting 11-13 when i baby it.i only got 15k on it now

My Milage Was 20 Mpg. Before Propane. Just Insalled Proane Sofar Gained About 3-4 Mpg. TRY ALSO SWITCHING TO SYNTHETIC OIL.

I do run synthetic oil. Change it every 5K miles. And I change my air filter every 10K miles along with the fuel filter and trans filter.

my wife normally drives it around suburbia. i hand calced 13.25 just yesterday, right before paying 4.10/gallon :( . when i drive it, it's mostly highway(80%) with a little around town(20% at most) and i hand calced 16.7 :).

I normally get 18-20 on highway depending on how heavy my foot is.

hand calculated... that mpg is usually at 65-70 no towing

my truck is reading 21.3 right now around town thats with a S&B intake, PPE standard on level 4, stock 245s, and not sure if this really makes a difference but a undercover bed cover and when i fill up the range reads around 520-530

159 votes so far and they seem to be all over the place. I'd love to start a thread just from the guys who claim to be getting over 20 mpg to see exactly what their secrets/combinations are.

Summer's almost here, so I've started mixing about 3-4 gallons of filtered wvo per tank again. Does that count by decreasing my fuel purchases??? :)

I have just filled up, 20.623 gal for 257.6 miles = 12.49 mpg hand calulated average 36 miles freeway a day.

I average 12-14 towing my horse trailer and 18ish unloaded with a medium foot.

my truck is reading 21.3 right now around town thats with a S&B intake, PPE standard on level 4, stock 245s, and not sure if this really makes a difference but a undercover bed cover and when i fill up the range reads around 520-530

When you hand calculate it it will be off. Programmers throw off the DIC

159 votes so far and they seem to be all over the place. I'd love to start a thread just from the guys who claim to be getting over 20 mpg to see exactly what their secrets/combinations are.

Summer's almost here, so I've started mixing about 3-4 gallons of filtered wvo per tank again. Does that count by decreasing my fuel purchases??? :)

Look closely at my sig. That's the whole deal... including the fuel additive. Oh... and don't drive like you stole it... ;)

Randy, when you talk about resonator blocked and PCV re-routed, that wouldn't affect mpg, would it?

alright just got back from a nice highway drive with a couple of stops in between hand calculated it came out to 20.65mpg now for this size truck i am truly impressed to see that my wife dont understand why i was so happy:cool:.o and that was with the cruise set at 71mph.

Randy, when you talk about resonator blocked and PCV re-routed, that wouldn't affect mpg, would it?

Resonator block will improve performance slightly, which I always read as a positive toward mileage. Rerouting the PCV keeps oil residue out of your intercooler, which helps keep the engine cleaner. Not sure if this does anything to improve mileage. Neither will hurt your mileage. Blocking the EGR might drop your mileage though... I've heard that it improves, doesn't change, and hurts. Ultimately, I think it improves the mileage.

Hope this helps...

alright just got back from a nice highway drive with a couple of stops in between hand calculated it came out to 20.65mpg now for this size truck i am truly impressed to see that my wife dont understand why i was so happy:cool:.o and that was with the cruise set at 71mph.

Is there a diffrence between you guys on the right hand side of the country to us on the left hand side.I would love to get 20mph.

on a real long trip i got 23 mpg. but haven't seen that again. right now running 285's and the triple dog set on performance i am getting 18-19.5 mpg and thats a mixture of highway and city driving as well as getting on to it a few times. would love to get back to 20-23 mpg

not realy sure but i will be driving that same route this weekend and im gonna see if its the same.

not realy sure but i will be driving that same route this weekend and im gonna see if its the same.

Hey banshee, how's the electric fan setup holding up so far?

20 on average....I have seen 21.3 on dash...waiting to hand calc it this week when I finally fill up again..

Running a mileage tune from www.Mcratracing.com site ...went from 12mpg:eek:

seems the faster I go the better it is...80mph ..I had to relearn to drive(keep my foot out of it) to get these milages


Capt

i dont have electric fans?maybe a mix up i knw there another member called banshee ....... that could be him.

same here

can get 20 @ 50-55 mph with bullydog. interstate about 18 @ 70 - 80 mph. the k&n replacement air filter helped bout as much as the programmer. Bullydog on stock = 18 on tow haul = 19 and performance = 20. these are hand calculated.

Around 12.5 to 13 MPG pulling the camper at speeds around 70 MPH. Best I ever got was about 22.8 MPG on flat ground and that was with about 600 LBS of hunting supplies in the truck. Generally around the house here ( in the mountains) I get from about 16 MPG to 18.5 MPG according to how I drive. All of those figures are hand calculated.

Computer reads 21.0 right now. That is for normal suburban driving in Phoenix. I have checked computer in the past with hand calculations, and it is plenty close.

2500HD crew cab short box, as it came from Chevy factory.

Bill

When I drive it cross country from Arizona to Minnesota or visa versa I average about 75 mph, with about a thousand pound load. Depending on winds, I will average from 18-21 mpg, full trip.

2500HD crew cab short box, as it came from Chevy factory.

Bill

When I drive it at 60-63 mpg steady, pure highway, I get anywhere from 22-24.5 mpg. I know you have a hard time believing 24.5 because I have a hard time believing 24.5 but I have had it happen a couple of times. The fuel economy I get from this truck is amazing.

2500HD crew cab short box, as it came from Chevy factory.

Bill

Oops. Forgot to mention that my truck is TWO wheel drive. My buddy has the same truck in 4WD and he seems to get about 2 mpg less, but his driving style might be different than mine. Like me, though, he is a conservative driver.

2500 HD crew cab short box 2WD(!), as it came from Chevy factory.

Sorry about all the posts.

Bill

Billk, What year is your truck?

What is the cool my dmax cia

Billk, What year is your truck?

It is a 2004. I have owned this truck since Day 1. These numbers are real - I understand the games some people play with fuel economy and how some folks can kid themselves. I have been blown away by the fuel economy of this truck ever since I bought it.

I am running Michelin LTX tires, slightly oversize, so I adjust-up whatever mileage the computer says by about 5% to account for the larger rolling diameter. The bigger tires have not cost me anything compared to the OEM Bridgestones. I never run 50/80 except when going cross-country, and have a load. Too bouncy for normal driving otherwise. I am a very conservative driver with this truck, especially when going cross-country, as I value the fuel economy.

I see you have 2005 2WD with LLY engine. What are you getting for fuel economy? (I have not read all of this thread, so you may have already posted your numbers.)

Bill

I get not great but good mileage out of my truck.
Check my garage for a snapshot of what i'm getting. All hand calculated.
Mix highway/country running at 65mph highway.

Just averaged 11-12 towing a 12' flatbed with two hunting quads from Gilbert to Alpine and back. Clutch fan on alot even when it was 65 degrees out. Lame.... I usually get between 12 and 13 unloaded. 13.8 was the best ever!!! Hand calculated.

I selected the 19-20mpg range. I got 19.4mpg on my last tank with an average 34mph. Most of my miles are highway and I'm running an EFILive tune for economy and keep my foot out of it and drive 60-65mph on the highway.

Just ran from NE Ohio to Richmond and back pulling my 28' camper. Trailer weighs about 7500 lbs. loaded and I was carrying two generators and a whole bunch of other stuff. Had the Predator set on the 40 HP towing tune. I ran 65 mph and averaged just a tick over 12mpg(hand calc'd). Using the 65 HP tune over the winter, I got just under 18mpg going back and forth to work. 70% highway 30% city.........:D

Just ran from NE Ohio to Richmond and back pulling my 28' camper. Trailer weighs about 7500 lbs. loaded and I was carrying two generators and a whole bunch of other stuff. Had the Predator set on the 40 HP towing tune. I ran 65 mph and averaged just a tick over 12mpg(hand calc'd). Using the 65 HP tune over the winter, I got just under 18mpg going back and forth to work. 70% highway 30% city.........:D

Best I've ever seen towing was with my Predator set on +40 towing, running between 60 to 65 mph, and the mileage came out (hand calc'ed) at slightly above 14 mpg. More often than not, it's between 11.5 to 13.5. My TT is 24' and weighs somewhere between 7000-8500 lbs.

There ain't a whole lot of flat ground on that stretch. On the way back, I was running into 30 mph headwinds. Overall, not too disappointed..

i average around 17 overall get 20 on long trips and 15 or so while towing

Hand calculated, with my PPE set on #6..(220)...I am getting a steady 17.5 in town and 21.5 Hwy with the cruise set at 75MPH
Thats MY story, and Im stickn' to it!!

I get better than 20 on the highway - but I do 55 most of the time - it's the speed limit between work and back...

jeff

I must really need to lighten the pedal or something?????

I must really need to lighten the pedal or something?????

Or learn how to stretch the truth. :D Just like I tell the little woman I am a full 6 inches. ;)

Or learn how to stretch the truth. :D Just like I tell the little woman I am a full 6 inches. ;)


This is why women can't judge distances. Every guy tells them they're getting 10"!!!! :D

17-18 in town last trip on the interstate 23-24

Just did the math on the last several months receipts, came out to 15.88 mpg.
usually driving empty on the freeway around 70 mph.

This is why women can't judge distances. Every guy tells them they're getting 10"!!

Yeah, but in my experience they can smell bullshit from a great distance away :rolleyes:

We men tend to believe our own BS mor'n we should.

Just like with the go pedal, it's how you use what you have that counts! :D

12-13 in town and 17-18 Hwy since I made the switch to ULSD.....Hand Calculated

14-15 (dash) 16-17 (H.C.) with my 285's on, 17-18 (dash) ? (H.C.) with my new 245's on. everything else stock.

Yeah, but in my experience they can smell bullshit from a great distance away :rolleyes:

We men tend to believe our own BS mor'n we should.

Just like with the go pedal, it's how you use what you have that counts! :D

Yeah I have to use the go pedal quite frequently to compensate. :D

Truck runs great! syn oil all around except tranny, will be changing that soon, - 13.5 in Middleton Idaho

I get 16-17 running on the highway at 75 mph in W. PA. This is h.c. with the mods in the sig. With the price of fuel, I am kinda wishing the truck wasn't lifted and running 35's!!!

Well hand calc'ed I got 23 miles to the gallon. 362 miles on 24.5 gallons. That works out to 23 miles per gallon. I am amazed!!!

Well, I'd like to thank everyone that's participated so far.

I think if I do this again I'll have to stipulate either 4x4 or 2wd. I think the numbers are a bit squewed at the high end because of 2wd vehicles. We'll see.

It all depends but my normal ave is 14ish. Yesterday towing a boat to Reno I got 9 MPG up and over 20 on the way back empty.

Well hand calc'ed I got 23 miles to the gallon. 362 miles on 24.5 gallons. That works out to 23 miles per gallon. I am amazed!!!


Umm. 362 miles to 24.5 gallons is only 14.77 miles per gallon

Umm. 362 miles to 24.5 gallons is only 14.77 miles per gallon


Hmmmm, must be that new math.:rolleyes:

I love the warm weather we are finally getting. The quicker mine gets up to temp, the better mileage I get. Still expensive, but much better then the 6.0 would get in the 2500.

i am getting 25mpg highway i am using a new additive from BPI it works awesome

I was getting 17-18mpg until I made a 200 mile trip this weekend and something went wrong. I only got around 9.5 to 10 mpg...........now it gets 0.0mpg because it won't run

I wish I could find out why my truck only gets 12 to 13 on the highway I was do only 14 this sucks so if any one can help that would be great.

How heavy is your foot?
What's your average speed on the highway?
What RPM's does the trans shift?

Fact:
Drive like Mr. Magoo good mileage
Drive like you stole it poor mileage

Keep your speed down and the RPM's under 2k and you should see an improvement.