I own a new 2007 Silverado with a Duramax 6.6 with a Allison 6 speed. I only have 500 miles on it. I just did a 114 mile trip empty on 5.4 gallons of fuel. That equates to 21 mpg. I'm so pleased with the fuel burn. I made sure I only went 5 over speed limit to really test what it's capable of. Next time I'm going to run it out more and see what the difference is.

I own a new 2007 Silverado with a Duramax 6.6 with a Allison 6 speed. I only have 500 miles on it. I just did a 114 mile trip empty on 5.4 gallons of fuel. That equates to 21 mpg. I'm so pleased with the fuel burn. I made sure I only went 5 over speed limit to really test what it's capable of. Next time I'm going to run it out more and see what the difference is.

What model? 2 WD or 4 WD?

Fwd

You go much over 70 mph and the milage starts to go down. 65-70 seems to be the sweet spot on mine.

I heard the new ones got better fuel milage. i have a 03 cc 4wd and only get about 15. That would be a significant improvement over mine. That would almost make up the diference in payment

A buddy bought the 6.0 gas 2007 2500 same time as I bought mine. He reports 12mpg town, 14mpg highway. Everytime I hear that - glad I got the D-Max.

;)

A buddy bought the 6.0 gas 2007 2500 same time as I bought mine. He reports 12mpg town, 14mpg highway. Everytime I hear that - glad I got the D-Max.

;)

Im still getting 13ish all highway, even worse in town.
Maybe I should have bought the 6.0.
I sure could buy alot of gas for the $8500 difference.


Future plans are EFI Live, egr block off & dpf delete exhaust SOON !!!!

oil burner how fast was 5 over the speed limit where yu where . how do you no you used exatley 5.4 gallons of fuel ?

Thats about what I'm getting.. I guy I saw at the gas station the other day said I wouldn't notice a difference until I got about 40K on my truck... It has 1K on it now so I got a while to go..

I've got 1400 miles on our new 2500 HD LB 4WD. The best I have ever seen on the DIC is 14.9.

I've got 3,500 miles and the worst I have got out of a tank was 16.4 hand calculated, and that was my first fill up when the truck was brand new. Now even if I hammer it I get 17 average, and if I'm nice to it 19+. Last tank was 450 miles out of 23 gallons = 19.5mpg. Nothing special about my truck, how are these trucks so wide spread in mpg?:confuzeld

As for my speed I stayed between 65 and 70 mph. How I know how much fuel I used I topped off to the point I couldn't take any more fuel and when I got to my destination I topped off again until it couldn't take any more fuel and did the math.

my 2007.5 longbox 4x4 3500 crewcab is getting a mixed mpg around town and on the highway. It varies from 12 - 17mpg. I thought it would be much better. My brother has a 3500 quadcab Dodge 4x4 with the 5.9L and he's up around 24-25mpg. He drops to 10mpg when hauling his 10.5' camper with a single slide-out in the mountain passes.

I just recently finished an 1100m trip, hand calc'ed at 19.4, 90/10 highway/city, with roughly 1900m on the ODO total. Avg'ed 65-68 mph. VERY happy so far.

my 2007.5 longbox 4x4 3500 crewcab is getting a mixed mpg around town and on the highway. It varies from 12 - 17mpg. I thought it would be much better. My brother has a 3500 quadcab Dodge 4x4 with the 5.9L and he's up around 24-25mpg. He drops to 10mpg when hauling his 10.5' camper with a single slide-out in the mountain passes.


Huh?? 24-25
Step 1. Top of hill, press reset.
Step 2. Coast to bottom of hill.
Step 3. Record read out.
Step 4. Tell everyone you get 24-25.

As for my speed I stayed between 65 and 70 mph. How I know how much fuel I used I topped off to the point I couldn't take any more fuel and when I got to my destination I topped off again until it couldn't take any more fuel and did the math.

Hi Jim,..you better know who this is, your Dad of course. When you called me from Baltimore & told me what mileage you got, all I remember was your F250 Triton V-10 never left the Gas Station.:( (maybe 10 mpg) maybe. Glad you like it, it's quite a truck, after you let me drive it before you left, I thought what a great ride compared to my JK Wrangler 4 Door. And I'm only getting around 14 mpg in it(but it does climb Rocks great):D.
A&A Auto called today and your ProComp A/T's 285/75/16's will be in tomorrow, can't wait to see them on that beast. My Son don't have any pic's of his Truck but his father does....:D

PS,..what's the MPG in that Jet your flying now,:eek:



http://img.photobucket.com/albums/v647/nam676869/Picture024.jpg
http://img.photobucket.com/albums/v647/nam676869/Picture039.jpg
http://img.photobucket.com/albums/v647/nam676869/DSCF0024-1-1.jpg
http://img.photobucket.com/albums/v647/nam676869/DSCF0022-1-1.jpg
And here's his Dad's Toyhttp://img.photobucket.com/albums/v647/nam676869/2007-09-23-JRU-075800x600-3.jpg

When my 2007.5 cc 4wd (stock) had about 500 miles on it, I took a 300 mile round trip on a hilly interstate and got just over 20 mpg. Now I routinely get 13 -14 around town and up to about 20 on the road. I am told the best is yet to come because the engine is not truly broken in until 10k miles or more. I am very happy with my fuel mileage keeping in mind this is a 3/4 ton truck!

my 2008 cc dually at best had gotten 525 miles on a tnak of fuel... some of these number are pretty outstanding.. hmmmmmm

My mileage has stayed around 17.6 avg after 3000 miles.

nam6869, nice JK. I traded my 07 JK 4 door for the Silverado. I now have a 94 YJ I made my trail rig and tow to trails.

Yea dad, I burn 1700 gallons of fuel in 7 hours at 580 mph. I guess that's good.

New to the forum.
2008 GMC cc 2500. 1900 miles and average mpg is 11. :mad: Checked by hand every fill up. I don't understand why there is such a variance b/t all these trucks.

No mods yet just 285's

Hello,
This is my first post. I just purchased my 07.5 LTZ CC 2wd about 3 weeks ago. I only have 785 miles on it and I am only getting 13 miles a gallon unloaded. This is driving it keeping the RPM's under 2000 city and a little highway. I don't know how you guys are getting such great mileage compared to mine. The truck is completley stock except the dealer put on the 17" GM chrome rims on it. Tires are 265 70 17. I have calculated the mileage by hand and with the DIC but still come up with no better then 13 miles a gallon. Do I need to have my truck checked? If so what should be checked? Love the truck otherwise.

Thanks,
RTDuramax

Hi I've got 07.5 GMC 2500 6.6. lmm.Currently getting 16.5 in the oilfield 250km a day all dirt roads.And 23MPG on the highway through the mountains on the last trip.Has a juice with attitude on the first setting.Currently very happy coming from a cummins.Good job GMC.This truck only has 4000 miles.

I have an 03 crew cab 4x4 and took it on a trip wasn't really trying to save fuel running around 74mph the whole time went 200.3 miles and filled up with 10.7 gallons of fuel thats approx 20.03 and I had a max speed of 92.9 mph according to my gps I was playing around with a rice burner.

I have a 2008 GMC 6" lift on 35's. The motor is completley stock. 2800 miles and i'm getting 11mpg hand calculated. Can there be such a variance because of driving style? I drive mine like I stole it.

Ok here is the deal. I have heard anywhere from 21 hwy to 12 hwy. The biggest difference on fuel economy is how you, the owner, drive your truck (besides tunes). If you can keep your foot out of the floor (I know it's really hard) that is most of where the mileage comes from. Also when you reset your DIC. The average in the DIC only comes up about .2 every 15 miles. So, good luck, and who cares about economy anyway, it's like driving a sports car with a bed you never have to make. Cheers!

New to the forum.
2008 GMC cc 2500. 1900 miles and average mpg is 11. :mad: Checked by hand every fill up. I don't understand why there is such a variance b/t all these trucks.

No mods yet just 285's

tbfountain, I know this will not make a huge impact, but have you had your speedo corrected for the larger tires? If you are not taking them into account when you hand calculate, it could throw you off a bit.

ok trip to main total miles around 4000 miles of driving mostly pulling are 30 ft cougar travel trailer total wieght pass,dogs and trailer around 8700 lbs. we averaged 11.50 for the total trip. around town pulling my work trailer I get around 14 the trailer wieghs in at apx 2500 lbs hwy with no trailer getting about 19 to 20 around town no trailer getting around 15 total average comes in around 15 miles per gal with all 6400 miles driven so far truck is total stock. I will say this if you have a led foot you watch the fuel meeter go down. 2500 4 door regular bed not the long bed 4x4 with a cab on the bed 2007 new body style .I love this truck. I traded in my v10 ford f250 for it best thing I ever did.

My mileage has been pretty lousy through the first 1500 miles. I get 11 to 11.5 in 90% city driving, empty. I drive like a grandma most of the time, so I can't attribute it to driving style.

Recently took a long trip towing a small trailer (about 2,000 lbs) with another 1200 lbs in the truck. Got 12-13 going 70-75 over the Snoqualmie pass in WA. I'm not so concerned about the mileage on my trip, I was going a little fast. But the around town mileage is pretty brutal, I was hoping for closer to 14.

My most recent tank is holding at 13.4, but there has been more than normal highway driving. I'm hoping that the mileage will continue to hold in the 13-14 range as the engine breaks in.

As my daily driver (empty), mix between hiway and city, I get anywhere between 15-16mpg. Where I live in Cali is not flat since I have to go up and down through some hills and that can eat up some mpgs. On long road trips mainly hiway, I have seen 19+. I drive mostly below 70 and try to use my cruise control as much as I can. I've got around 6K on the truck now. Very happy on my mpgs, especially compared to my previous gasser truck.

-Ronnie

18city 22plus hyway at 70mph or 500 plus miles to a tank EFI and no DPF

Hello,
This is my first post. I just purchased my 07.5 LTZ CC 2wd about 3 weeks ago. I only have 785 miles on it and I am only getting 13 miles a gallon unloaded. This is driving it keeping the RPM's under 2000 city and a little highway. I don't know how you guys are getting such great mileage compared to mine. The truck is completley stock except the dealer put on the 17" GM chrome rims on it. Tires are 265 70 17. I have calculated the mileage by hand and with the DIC but still come up with no better then 13 miles a gallon. Do I need to have my truck checked? If so what should be checked? Love the truck otherwise.

Thanks,
RTDuramax


Hey RT: Hang in there; I had the same thing going on with my 07.5 cc 4wd, until I hit 3000 mi or so, and saw a big improvement. My highway only is now in the 19-20 range, but my overall average is around 14-15 mpg. It is disheartening to watch the MPG when regen is going on. BTW, my numbers are from the DIC, I have not hand calculated, but in my experience (99 Sierra 5.3 and 03 Silverado HD 6.0), GM DIC is very accurate as long as you don't change tire sizes. Write back when you get to 4k.

I last reset my DIC milage about 1,500 miles ago. Now have about 3,700 miles on it. Decided to leave the DIC alone and see what the mileage looks like long term. I'm getting 15.4 miles now and it has been increasing slowly. This average includes two trips to Lake Tahoe pulling a 12K boat, city driving, and a few commutes to work on the highway - so its a mix of all kinds of driving. I've been running biodiesel in some form since I bought the truck. Started with B100 in the summer, and am now running B20. Mileage seemed to go up faster with the B20 in the tank.

I am trying my best to keep my foot out of it, 'cause I know that plays a big factor in mileage. It's really hard sometimes, especially stopped next to a Furd.:D

Hey RT: Hang in there; I had the same thing going on with my 07.5 cc 4wd, until I hit 3000 mi or so, and saw a big improvement. My highway only is now in the 19-20 range, but my overall average is around 14-15 mpg. It is disheartening to watch the MPG when regen is going on. BTW, my numbers are from the DIC, I have not hand calculated, but in my experience (99 Sierra 5.3 and 03 Silverado HD 6.0), GM DIC is very accurate as long as you don't change tire sizes. Write back when you get to 4k.


I hope you are right. If it stays at 11-12mpg indefinately I'll be very disappointed. I love the power and everything, but part of the reason I chose the Duramax over a Ford PSD or even a V10 was the better mileage. I hope I didn't make a mistake.

Started with B100 in the summer, and am now running B20. Mileage seemed to go up faster with the B20 in the tank.


So you have no concerns the GM only warranties to run B5 !?

;)

Thinking of upgrading this year and am researching. Generally speaking, how much difference can one expect in fuel mileage between a 3500 single rear wheel and 3500 dual rear wheel?

So you have no concerns the GM only warranties to run B5 !?

;)

Don't get me started on that...Censored

I'll run B100 without hesitation. Only problem is this time of year, B100 will turn to Crisco in my tank at night, so I'm runnin' B20 until springtime.

Any mods required to run B20? Safeway pumps have B20 around here now. I have been getting B99 at the local CFN trucking diesel stop in a 5 gallon diesel container, then adding 5% when I fuel.

;)

Got 21 mpg on 600 mile round trip and had averaged 15.4 in town when truck was stock. With lift, tires and PPE I'm Averaging 12mpg with 50/50 open road and city driving. Best road trip was 16.4 with lift and PPE on level 4. Not too bad since I'm still breaking her in.:cool:

I traded my 05 3500 DRW for an 08 F450 in July. The 450 gets 12.2 all around MPG. I have 4.88 gears so it just goes down after 62 MPH. I just thought I would share that info so you guys feel better about the milage. All the ford guys I talk to are not too pleased with the variance between trucks either.
The 05 DMAX DRW only got 16 with a banks six gun bundle. I'm going to add a gear vendors soon since it is about the only thing that won't f up the warranty.

I traded my 05 3500 DRW for an 08 F450 in July. The 450 gets 12.2 all around MPG. I have 4.88 gears so it just goes down after 62 MPH. I just thought I would share that info so you guys feel better about the milage. All the ford guys I talk to are not too pleased with the variance between trucks either.
The 05 DMAX DRW only got 16 with a banks six gun bundle. I'm going to add a gear vendors soon since it is about the only thing that won't f up the warranty.


I'm getting 12.5 all around in my truck; a SRW with 3.73s. So, you didn't make me feel any better. Thanks for trying though.

Congrats on the new truck. That thing is a hauling machine! You might feel better knowing you are getting the same mileage as I am with a truck that weights 2,000lbs more and has lower gears.

GlockWRX,
Man I'm sorry to hear that your MPG is that bad. The emmisions crap has truely ruined the good ole days of diesel pickups. Seems like just yesterday diesel was $.95 and the trucks got better average MPG. I guess now we pay $8000.00 more for sentimental reasons. I hope your DMAX gets better with age.

my mileage has almost doubled since I got it at first it was getting 11 to 12 highway now getting around 20 highway my guess is that it has to do with break in and a little easier driving by me
07.5 srw 4x4 cc 10000 miles

I get about 15.3 mpg on city/highway, 5 miles to/from work and around town. I dont know what I am getting on the highway without a trailer. I get anywhere from 12.2mph to 10.1 mpg pulling a 28 ft enclosed car trailer (7000lbs) depending on which way the winds are coming from.

Has anyone looked behind their grille on the Chevy Model? There are huge air gaps on both sides of the rad/intercooler. I cut steel sheets and bolted them in, to block the air from entering the engine compartment. Next I am going to block off the top section of the grille with plexiglass and also the lower section to see if I can get better mpg on the highway. I am going to leave the middle section open to add some more air for cooling and also leave the lower section open on the bumper for air. There is at least 12 inch space between grille and rad/intercooler. This acts as a huge parachute. Now all the air is forced through the intercooler and the grille. The truck still gets to 210 but I notice less resistance in the truck when I am running down the road. Amazing for $10 and a cut off wheel.

I have a 2008 Silverado 2500 HD 2WD with a Duramax 6.6 with 500 miles on it and the computer is saying I am averaging 15.5 mpg. I mainly drive highway but some around town as well. Hoping it will get better.

Cole

Just got back from a trip to the Grand Canyon... I have not reset the DIC since new... left with just over 500 miles on the clock.... now just over 2000 miles after the trip. DIC currently reads 16.8. It was under 12.5-13.3 for the first 500 miles. The improvement has been pretty dramatic... albeit lots of highway to the ol canyon.

6800 miles and I am getting between 16.5 and 17 around town. Some two lane but stopping all the time. I have not done the interstate yet or hauled a trailer. In March will be hauling a four horse trailer about 3600 miles. Should be interesting.

Jim

Have about 2500m on the odo right now. Did a 1100m week a couple weeks back; avg'ed 19.4 hand calc'ed. Last Friday, went into Syracuse and back (about 360m) avg'ed 21.9 out and 21 back..................I'd say that I'm happy with that!!

would youz all like some Cheese und Krackers with that wine..??

don't sweat the mpg in the beginning...the LBZ's did the same and for many not till 20-35k before ti started to get better. These are Diesels..they like to work..so give em some work. the harder ya work em the sooner your mpg will start to rise.

06 CCSB - MT / Full tank / no wind / prairrie

would youz all like some Cheese und Krackers with that whine..??:D

Don't sweat the mpg in the beginning...the LBZ's did the same and for many not till 20-35k before they started to get better. These are Diesels..they like to work..so give em some work. Seems the harder ya work em the sooner your mpg will start to rise..

06 CCSB - MT / Full tank / no wind / prairrie 120kmh (73mph) - 18.5mpg

MT / full Tank / no wind / Calgary to Kamploops (Rockies),
100 - 105 kph - 21.4 mpg (surprisingly)
DIC..but hand calc is almost always within .2 of DIC

My mileage is now at 99080km (61,000 miles approx)
Banks at Level 3 / Sirius on 103 (that helps..!!) :p:
No Issues. LOVIN IT.!!

cheers,
stk

well i have 3 diesel rigs
d/a suburban gets 19hwy 15town

01 dodge 6speed 24hwy under 70 17city (put 180 k miles) hand calc
3.55 gears 315 tires (cal for tires) edge, boost fooler, exhaust,
got 10 mpg towing from durango CO to Tacoma Wa going much to fast 27hrs including a 2hr nap (loved the cummins not the truck)

08 ford f350 3.73 20 inch wheels stock 11city
16 hwy, pulled my 5er to florance Or from Buckley Wa and got 6.7mpg at 65mph, cost me over 400 in fuel double what it took in the dodge!
my friend got 11 in his 07 classic towing a larger 5er
truck has 8k miles on it and i use it for work hauling tractors and record all milage hauling and that is over 7k miles with a trailer in the last 3 months. now i have a bigger payment and my fuel bill has doubled!

Dont get me wrong if i was that concerned about fuel milage i would have kept my Jetta TDI it got 47mpg for my wife 40 for me but could not quite pull my 5er

my trailer weight is about 15k loaded gvwr is 18,500 it is a cyclone tripple axle.
maybe i shoud have bought gmc. Ford has me scared to put on any mod they have been flagging trucks and voiding warranty

Dont get me wrong if i was that concerned about fuel milage i would have kept my Jetta TDI it got 47mpg for my wife 40 for me but could not quite pull my 5er


I resemble that remark...!! and have seriously considered buying one, used, across the line (south) now that our dollar is above par with you folks. (2001 -2003 std.) Awesome little machine and there are times I would like to have the feel of a 5 spd stick shift in my right hand. ;) We shall see.

But on long trips solo and where I travel .. I'll still take the truck ... can't imagine hitting a deer with a Jetta. :eek:

cheers,

stk

arnt the deer big enough up there that you could drive a jetta thru there legs! :D

Was on the "diesel page" looking at the mileage for the lmm and the guys posting there aren't getting close to what is being posted by the majority on this site.:confused:

Got me a little worried as I will be picking up a new 08 lmm/da next Tuesday, duplicate to what I have now. (unless I talk myself out of it.)

Trading in an "03" that gets 20 - 21 mpg hwy for an "08" that will get ???

Even though I remember when I first started driving the "03" it was in the 16/17 range on the highway.

Maybe just a little buyer remorse before I actually spend the money:rolleyes:

It's all over the map, no doubt (although I'm happy see my earlier post). A couple things for sure, more mileage generally equates to better mpg's, and also just how heavy the right foot it..................other factors, driving habits, etc aside.

i ran a tank of fuel combining towing a closed trailer and without the tow. truck is set up with edgeEZ set low, 285's, kn air box and mbrp exhaust. i got about 15.8 and that was goosing it up some decent grades. not bad for a corvette with a truck body.

Was on the "diesel page" looking at the mileage for the lmm and the guys posting there aren't getting close to what is being posted by the majority on this site.:confused:

Got me a little worried as I will be picking up a new 08 lmm/da next Tuesday, duplicate to what I have now. (unless I talk myself out of it.)

Trading in an "03" that gets 20 - 21 mpg hwy for an "08" that will get ???

Even though I remember when I first started driving the "03" it was in the 16/17 range on the highway.

Maybe just a little buyer remorse before I actually spend the money:rolleyes:

:smashfrea:smashfrea i was just looking in the spring at 08 ford before i knew it i trade my 03 gmc in for king ranch loaded had it a month hated it 5 month later
got lmm loaded like it but if i had all to do again i would kept my 03 and brought the lmm