I will be upgrading my 1/2 ton to a 3/4 ton soon with the 6.6 and was wondering what kind of MPGS you guys are seeing in the city? I have the 6.2 right now with 33's and getting around 11 or 12 in town and also on the highway doing 70 to 80. When i pull my 9000 trailer i got 7mpg doing 70 for an 8hr trip. I plan on using the stock wheels and tires on the 6.6 and hoping for at least 18 to 20 down the interstate at 70 and at least 14 in town.
I had an 07 DMax 4x4 ext. cab LWB (stock/no mods) as a work truck for a year. On highway, with no load, I'd get around 21 MPG's.
Also had an 08 DMax 4x4 Crew cab (stock/no mods) and it would get about 18 MPG's, but my dad's 08 DMax Crew is exactly the same except LWB and he gets about 20-21 MPG's with no load.
I've decided that I probably could have gotten better mileage on both trucks if I'd kept my foot off the floor a little more often. Awesome trucks though...
I just test drove a 2500HD with the 6.6 and it had a very nice feel to it. I was skeptical because i have a 6.2 that will shit and get, but was very suprised by the feel of the diesel engine and tranny
Just about any handheld tuner can add triple-digit HP gains... kinda crazy, but they work.
I've also heard that diesels get better MPG when towing vs. gas engines. I can't say I've personally seen that, since I don't have a Duramax ... maybe in a few years.
Don't drive in the city much, but about 14-15 from what I've seen. After 8000mi I'm averaging 19mpg mixed suburban and freeway commuting. Mountain highway either empty or level filled bed I started out about 20mpg new, and my last 500 mile trip averaged 22.5 mpg. With 11,000lb 5th wheel I got 10.9mpg, and 7000lb travel trailer it was 13.3. This was also mostly mountain highway driving and some forest service road.
The milage just slowly keeps getting better, so I don't think is fully broken in yet.
Haven't seen too many (or any) 6.6L owners with Fuelly badges. Just made mine since I have less than 1k on my truck. I bring this up because it always seems like people writing about mileage don't have anything to backup their claims, and the discussions go more in a bragging direction. If you've keep a good log it gives a bit of credence to any claims you make.
I started out at roughly 15mpg in town, a few uprades... CAI, Turbomouthpiece (For LLY), 4" exhaust turbo back, and synthetic oil in engine/tranny/rear diff. I raised my intown mpg to about 18 hand calc'd. On the highway I am roughly 20-21mpg unloaded. With a tuner you could get up to about 23-24 unloaded on the highway. Dont go by the DIC in the dash, that thing is way off.
I have a little over 1,000 miles on it now...i am averaging 11mpg ! I tow a 4500 pound trailer 5 days a week city & highway mix. Is this normal? Bone stock.
Just about any handheld tuner can add triple-digit HP gains... kinda crazy, but they work.
I've also heard that diesels get better MPG when towing vs. gas engines. I can't say I've personally seen that, since I don't have a Duramax ... maybe in a few years.
If you get it tuned (efi live not a hand held) 22-25 mpg highway empty. My mom and dad took my dmax on a trip and where getting 17 to 18 pulling a trailer with motorcycles in it up to Vermont so all hills to
Yup, at 65 MPH. It doesn't change much at 70, either. I did a little towing today, and my light load (3000 lbs) didn't really have an effect on the fuel mileage.
I don't have one (maybe some day), but from what I've seen in my research the Duramax gets better economy than the Powerstroke and even the Cummins. What I've seen is most people see about mid to high teens city and low 20's highway.
^^^ 5k is weaksauce, your dmax cant eve feel it BTW welcome to the diesel club! I tow my horse trailer about 10k and use tow haul mode , its great and pretty much stops the truck for you. I will be getting efi live this month and one of my tunes will be a turbo break !!!
have a 2002 chevy Duramax crew cab long bed that is used to pull a 16ft gooseneck trailer to haul cattle and a 28ft camper the truck averages 16mpg but then again it has a 4" exhaust, edge juice with attitude, and K&N filter and always use tow haul when towing and to beat the powerstoke and cummins off the line when they want to race
I recently bought an 07 Chevy 2500HD ext cab long box with the 6.6 Duramax and I am only averaging 13-14 mpg (around 15 hwy). I actually checked this with fuel usage and mileage too not going off what the computer says. From what I am reading, that sounds pretty low. Truck appears to be running great just getting bad mileage. Any ideas why? Any suggestions on a modification or chip I could install to boost mileage?
I would suggest all new fluids, full synthetic, as well as a new fuel filter and a few bottles of diesel kleen. My 07 diesel is a crew cab long box dually, 200k miles, and she regularly gets 14-17 mpg.
Tuning might help, but that's another 500 -1000 dollars.
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