I am going to pick -up my brand new '05 crew cab 4x4 duramax tonite...what kind of mileage are you guys getting with these trucks? Do the tuner chips really help mileage? Thanks-cbarten

Nothing at all helps milage other then your right foot. Most everyone who is truthfull is seeing arounr 14-16 city and 16-19 highway. Towing is another story, all depends on size and weight.
Dan

Ditto what dwrat said! ):h A better flowing exhaust seems to yield some mpg improvements as well. Problem with tuners is you can't help yourself with all that power under your foot. Mama JJ always gets higher mpg's than I do, wonder why? ):h JJ :)

Anyone really interested in getting a lot of mpg would buy a Honda Civic or similar. The stories of getting 22 or 23 mpg on these Duramax's are sea stories. Expect 14 to 15 mpg in town traffic. 17 to 18 on the highway. Overall I am getting about 4 mpg better than the 8.1 gasser I used to own. Fuel costs for most of us are a small part of the price of owning one of these things. Depreciation and insurance take a bigger bite from your take home than fuel. Considering the weight of these trucks they are just about as fuel efficient as the Honda Civic. (fuel consumption per pound)

"Considering the weight of these trucks they are just about as fuel efficient as the Honda Civic. (fuel consumption per pound)"

aka108, oh I like the sound of that. Picture a television commercial with a DMax towing a heavy load and the final statement is:

Duramax Diesel Trucks! Pound for pound the most fuel efficient vehicle on the road today! :ro)

GM might consider using that for marketing material. Sweet! JJ :)

...remember quite a while ago....oh, about 45+ years I guess; while travelling on a "family vacation", a Union Pacific Billboard advertising something like this: Our trains get 1,000 tons per gallon". Did not think too much about this until JJ came up with his marketing moniker...!

Credit aka108 with the inspiration. Note I've added it to my sig. Others are welcome to if they like. GM should jump all over this one! With gas prices being what they are people look at our trucks and think they are guzzlers and not fuel efficient. But the math doesn't lie. Pound for pound we do get mpg's as good as if not better than most compacts.

GM Boyz, you can contact ol JJ about his royalty check right here on the DP. ):h JJ :)

Anyone really interested in getting a lot of mpg would buy a Honda Civic or similar. The stories of getting 22 or 23 mpg on these Duramax's are sea stories. Expect 14 to 15 mpg in town traffic. 17 to 18 on the highway. Overall I am getting about 4 mpg better than the 8.1 gasser I used to own. Fuel costs for most of us are a small part of the price of owning one of these things. Depreciation and insurance take a bigger bite from your take home than fuel. Considering the weight of these trucks they are just about as fuel efficient as the Honda Civic. (fuel consumption per pound)

This is not a sea story, I got 21mpg hand calculated with cruise set at 72mph on my 05 LLY crew cab 2wd.

mpg highly speed sensitive. I get about 23 mpg at 55 mph once warmed up on level ground. Right around 20 mpg running just below 70 and 19 mpg running just over. Took it easy going michigan to florida and back....sometimes doing 65 mph sometimes doing 70 mph and averaged 19.9 mpg for the entire trip. This is with an 05 4x4 crew cab with the allison and the dmax. I believe a smaller 2wd model might do even better.

I also tow a 32ft tag along trailer with 2 race cars....around a 9000 lb addition.....and can get around 12 mpg doing 65-70 mph or even 13 taking it real easy on the highway.

Did either of you use the DP MPG Calculation method to compute your mpg's? ;) 18.5mpg was my most recent highway numbers at 70mph all interstate, mile marker dual validation method. Yea, full Quad A baby! ):h JJ :)

thanks guys!

I have an 05 lly 4X4 duramax. 300 mile round trip yesterday, hand calculated 20.2, computer 21. I achived this result with an quadzilla (90) hp tune, running 70-75 mph. 95% highway, 5% city. I have 8000 miles on her

mpg highly speed sensitive. I get about 23 mpg at 55 mph once warmed up on level ground. Right around 20 mpg running just below 70 and 19 mpg running just over. Took it easy going michigan to florida and back....sometimes doing 65 mph sometimes doing 70 mph and averaged 19.9 mpg for the entire trip. This is with an 05 4x4 crew cab with the allison and the dmax. I believe a smaller 2wd model might do even better.

I also tow a 32ft tag along trailer with 2 race cars....around a 9000 lb addition.....and can get around 12 mpg doing 65-70 mph or even 13 taking it real easy on the highway.


This is EXACTLY what I get. I have a 04 4x4 crew cab. Yes, MPG is all in your right foot.

My truck (see sig) doesn't come close to any of these figures. I still love it, and the mileage is still better than a similar gasser, but I get 11-13 all around, and 7-8 towing my very tall v-nose toy hauler that weighs in at around 10K loaded up. I tow at 65-70 mph with the Edge on level 1 and most around town duty is done on level 3. I do have a fairly heavy foot, but no worse than a lot of folks here I'm sure. It does run nice but I wish I could see another 4-5 mpg across the board.



Gar

Just bought my 2wd swb crew almost 2 weeks ago. My first tank was 17.4mpg. That was some short hw runs but mostly city. I can already tell my second tank will be less since I have more bumper to bumper traffic on this one.

I do drive like a grandpa though!

Hope to get a full hw run soon, we'll see if it will get 20.

Just got over 700 miles on my 05 2500HD CC LWB D/A. Been getting 17.2 mixed city/hwy and 14.5 towing a 6500lb travel trailer. Much better than my old ford F-150.

I have just over 1200 miles on my new truck. 05 2500HD EX/SB D/ZF 6 speed
1st tank got 18.7 calculated. Pulled my 4700lb camper on second tank and it dropped
to 15.5. Right now the DIC is showing 21.4 average for tank #3.
After getting 11-12 empty with my 03 6.0 this is great.
I do tend to have a light right foot.
That and the manual tranny may be helping my mileage.

It seems Big Blue gets better mileage with me driving then McRat :confuzeld ):h

I seem to be averaging between 16 and 17 combined driving. My problem however is I am having just too much fun with the power this thing makes to get good millage. Oh well.....still better than the 1976 gasser I replaced which only got 10 at best, 6 pulling. Don't worry....be Happy!!:ro)

DP concensus seems to be that DIC's are not reliable for calculating mpg's. Best done by hand.

Kat, 411tq? JJ

The vette JJ, not the Dmax.

Oh yea, rocket #2! JJ

Hey JJ--Got to thinking about pound per pound fuel efficiency. While the DMAX is probably as efficient as a Honda Civic lb for lb, neither is as efficent as an 18 wheeler. These big rigs are getting 7 to 9 mpg hauling 80,000 lb. About what the DMAX gets hauling a 10 to 12 thousand pound trailer. GM and all the others need to think about that perhaps.

I was getting an average of 16-16.5 in Phoenix AZ Highway and city which was so so. I just recently removed Cat and added EGR plate/fingerstick. Also installed UNI airfilter. My last two tanks have went up to 18.5. My milage just passed 7500 so I don't know how much that contributed to it but I'm very happy.

5K kms (3K miles) on truck so far - calculating every tank the Quad A method.

city ~ 16 MPG - stop/go
hwy ~ 20 MPG - 75 miles/hr
tow ~ 12 MPG - 65 miles/hr - 7000# travel trailer

I will be a happy camper if it only gets better from here! :D

TCF

I also agree with otter04. I just got 22.2 mpg on a 410 mile useage and most of it was 50 to 55 mph country roads. About 60 was cold starts and short trips. I am confident that 23 mpg is what I get at a steady 50 to 55 mph. At 60-65 mph I get in the neighborhood of 21 mpg. I'm really in awe of the fuel mileage this truck is capable of.

It helps to keep the tires pumped up to towing pressure. I have 60 in the front but it bounces a bit more so will lower back to 55 psi.
05 CCSB D/A 4X4 with toneau.

well, I now have 1200 miles on the new truck...
17 highway 75-80 mph and the a/c on
22 country roads
Can't complain with those #'s!!!!
The only thing that I don't like is a 26 gallon tank...TOO SMALL!

05 lly 4X4 duramax w/2100 miles 35's w/6" lift 4x4 crew cab getting 10.8-11 MPG. What is wrong or is this normal with such low miles and larger tires. I've even had speedometer adjusted for the bigger tires and used the calculator to convert my numbers as I thout the onboard comp was off.

500 miles on my truck and I checked mileage manually. With mostly highway at 70-72 and a little in town driving I got 18.1 mpg. The DIC said 16.2. Not very accurate at all. Should get better from here I assume.


Dave

Two words: Weasel Piss

Helps my mileage considerably. I won't leave home without it now. Hell, on long trips, I just take a weasel with me. Magic, I tell ya.

:lol: :funnypost

I'll take a case if you can bottle and ship!!!

My average has been pretty crappy, 11-12 hand calculated in town mostly w/ Pred on 40 and 4100k on truck. Just filled up yesterday @ 23.15 gal. to 249.6 miles. Sucks -:t . Been runnin' additive too!! I think I may bring it in since i checked balance rates and saw #4 cyl. at -5.13 with a little fluctuation down to about -3.43. All the even # cylinders are between -2.45 and -3.89 at idle. Any opinions on a course of action?

Check was made in nuetral?
Hard to believe all those injectors are bad on the LLY.....

I just got a Bully Dog today. I would say get a programmer for sure!!! I just got one today and I was getting 22mph around town with my foot in it a little! I have only gotten to drive around a small amount with the tuner but i cant believe what a difference ive seen allready. Not to mention the truck is more fun to drive :ro) . I will respond back to this forum in a day or two once i get a longer chance to test out my gas milage.

I just picked my 05 crew cab, long bed, 4x4, D/A. Just over 700 miles and 19.1 average so far. I'm thrilled. Now to get a 4" exhaust, AFE airbox, Edge Juice w/Attitude and I'll be all set.

How the heck are people getting such good milage with a LLY?

My 01 averaged 18mpg. My 05 is lucky to get high 14 average. I drive the 05 easier than the 01.

I'm seing about 17-19 hand calculated(DIC is pretty close) through my first two tanks mostly around town and some freeway. I get my foot in it on a regular basis, but I try to coast up to stop signs & red lights and coast down hill when practical. More than anything I try not to waste momentum once I build it. Nothing will kill MPG worse than putting your foot in it to speed up to 60 then having to brake back down to 20 and put your foot right back in it again.

mpg highly speed sensitive. I get about 23 mpg at 55 mph once warmed up on level ground. Right around 20 mpg running just below 70 and 19 mpg running just over. Took it easy going michigan to florida and back....sometimes doing 65 mph sometimes doing 70 mph and averaged 19.9 mpg for the entire trip. This is with an 05 4x4 crew cab with the allison and the dmax. I believe a smaller 2wd model might do even better.

I also tow a 32ft tag along trailer with 2 race cars....around a 9000 lb addition.....and can get around 12 mpg doing 65-70 mph or even 13 taking it real easy on the highway.


I'm doing exactly the same, best case I even get 25. thats if I drive it like a old lady!

2 tanks thus far 1st tank was 15.5 mpg and the second was a round 16, I was heavy on it this past week, as I had just gotten it and wanted to see how it would take off. Most of my mileage has been around town and back rounds little highway.

These trucks are upwards of $40,000+ and I'm sure not your average 9-5 person who sits behind a desk would purchase this type of truck (there are exceptions). Point I'm getting to, does mpg really make that big of a difference with everyone. I burn between 20 and 24 gallons a week = $52. Even if diesel was $3.00 a gallon, $60-$70 a week wouldn't be bad. That's my $.02

My accord gets 16-17 around town, mid 20's on the highway. My Duramax gets 14 in town, 19-21 on the highway. 13-15 pulling a small trailer

On a 1000 mile trip the difference in fuel cost is <$30. with the comfort and convience going to the duramax.

Accords holds 2 people comfortably, 4 in a pinch, not much luggage, weights 3000 lbs.
Duramax crew cab holds 5 confortably, huge trunk (with taneu (sp) cover) weights 7000 lbs. Seems like the Duramax is delivering way more than the accord. Face it, the duramax gets better mileage than lots of much smaller SUV's. My dads Lexus Rx330 only gets a few mpg better in town or on the highway than my duramax, no reason to complain at all.

I just got a Bully Dog today. I would say get a programmer for sure!!! I just got one today and I was getting 22mph around town with my foot in it a little! I have only gotten to drive around a small amount with the tuner but i cant believe what a difference ive seen allready. Not to mention the truck is more fun to drive :ro) . I will respond back to this forum in a day or two once i get a longer chance to test out my gas milage.


I think you are being led around by the DIC.

The computer mileage calculation is completely useless once any box or tuner is brought into the picture. Mine claims upper 30' lower 40's on the freeway at 75 cruise. It aint anywhere near right.

.

I have a 2004 DA 2500HD - I'm getting about 13 in town and 18-20 on the road .. I pull a 35ft high profile Lakota 5er, mileage ranges from 10.5 (mountains) to 12 on level ground .... just turned 13,000 .. room for improvement .. no edge or other performance chip involved .. at this moment ... thinking about it ..

These trucks are upwards of $40,000+ and I'm sure not your average 9-5 person who sits behind a desk would purchase this type of truck (there are exceptions). Point I'm getting to, does mpg really make that big of a difference with everyone. I burn between 20 and 24 gallons a week = $52. Even if diesel was $3.00 a gallon, $60-$70 a week wouldn't be bad. That's my $.02

Think about it this way. Depreciation/mile. $40K/200,000 miles = $.20/mile depreciation. Fuel at $2.25/gal @ 13mpg avg. = $.17/mile. So, if you run 200K miles end up junking the truck, depreciation is costing as much or more/mile than fuel costs!! If you sold it at 100K miles for $10K depreciation would cost you $.30 mile, almost double fuel costs/mile

Point I'm getting to, does mpg really make that big of a difference with everyone. I burn between 20 and 24 gallons a week = $52. Even if diesel was $3.00 a gallon, $60-$70 a week wouldn't be bad. That's my $.02

Yep, MPG matters to me. Main reason is my last truck a 2001 Crew Cab Dually with the D/A got 18 mpg on my commute. My new 2005 Crew Cab Dually with the D/A has got a best todate of 14.9 mpg on the same drive.

That means I use 5 more gallons of fuel per week to get to work. The new truck should get the same mpg as the old one, especially if driven easier which it is. I never drove the last one to try to get good mpg. This truck when driven like the 01 was will only get 12mpg.

null

didn't alot of you guys install the plate and fingerstick? What ever became of that? Did it help with your milage? Did taking off the cat converter help?

MPG depends a LOT on the tires (width and diameter) on your truck! I am on a 5.000 miles tour from Louisiana to Montana and back. The cruise is set to 75 mph most of the time and I never get any better than 16 mpg. I got 19 mpg cruising through the Yellowstone Park with 45 mph (or less). I estimate that I lost 2....3 mpg with the 285/60/18 Nitto Terra Grapplers mounted on 10 inch wide wheels....