Chevy Duramax Fuel mileage

[rrbowman]

I am looking for an honest answer from actual campers. I am considering buying a used 2005-2008 Chevy 2500 w/Duramax with a Alison Tranny to tow a 10,000 - 11,000 Fifth Wheel. Those of you that have a combo similar, what kind of mileage do you get when towing and not towing? I know that is subjective because of driving styles but I consider myself a driver trying to get the best mileage. I have been told 22mpg around town and 16-18 when towing, is that possible?

[msjdbman]

My 08 LMM gets between 10-12 mpg depending on speed and wind. That`s at 17,000 combined weight with the 5er. I get the same mileage hauling my gooseneck with tractors on it at a combined weight of 26,500.

[Ezlife55]

04 LB7 gets 12 mpg towing 34.5 ft 5th wheel and 20 mpg on hwy not towing. Has new injectors (thx GM) and keeps on ticking without cat convertor or egr.

[hyattjlbb]

Agreed, my 2006 with the LBZ added about 2 MPG for both hauling and not. My LMM lacks a little of the power and mileage of the LBZ but supposedly burns cleaner. I do miss the soot when I get on her!

[wintersun]

Recommend you shorten your list to 2006 to early 2007.5 (Classic) trucks with the LBZ engine. It is a lot more reliable than the earlier engines or the later LMM one with its flawed emissions setup.

A friend with a 2005 was towing a 13.5k 5th wheel all over the western USA for years and getting 8-9 MPG. He added a Edge tuner and was getting 11 MPG towing the same trailer. Pretty good percentage increase in fuel economy.

MPG is going to be largely influenced by the weigh to the trailer, the amount of air drag, and the speed at which you drive down the highway. Air drag increasing with the square of speed so driving twice as fast means four times the air drag that needs to be overcome. That translates into more fuel burned.

I get a 10% hit in MPG with a 15 MPH headwind when driving at 65 MPH. I get a 15% hit with a 20 MPH headwind at that same speed. I would expect the same with the average 5th-wheel trailer as no RV generates more air drag than these trailers for their size.

[roman_traveler]

I get 25 mpg on my Duramax, 9 towing and 16 not towing.

RT

[Tystevens]

My mileage on my '06 Duramax was about the same as everyone else's --

17-18 at freeway speeds, 14.5 combined city/freeway driving (avg commuting for me), 10.5 - 12 towing. Best tank ever -- 19.7, cruise set at 60 mph for virtually the whole tank. Worst tank -- 8.5 mpg, towing the TT West on I70 across Utah into a brisk headwind going 75 mph the whole way (had a deadline to meet).

[butchfuzion]

I guess General Motors should contact their buyers, then they could double their claimed mileage for their trucks. See my earlier post.

[Uncle_Grumpy]

Have an 06 Duromax with 205,000 miles pulling a 28 ft low profile Excel that probably weighs 10000 lbs loaded. I get 13 mpg on flat ground at 62 mph. Highway unloaded at 65 I get 20. And an average of 18 highway and town. LOVE my truck.

[83trekker]

Me Again wrote:
Ford owns Cummins, don't you know? Chris

This just sarcasim right?

[hyattjlbb]

Have the '07 D'max, Crew, 4WD, with the 5er in the signature weighing about 14,000 depending on the trip. This last one was a little heavier for the 9 day haul and we towed on level ground from Minot, ND to Thief River Falls, MN, then to Detroit Lakes, MN and home. Needless to say a pretty flat run with temps in the 70's. Got right around 11.5 at 60 MPH (MN 55 MPH Limit) and dropped to 10.2 in ND running 65. Didn't have much wind the whole trip, so not a factor in the mileage. Normally run around 18 empty down the highway at 65-70 MPH.

[larry_barnhart]

houstown wrote:
Have a 3500 DRW Duramax that tows a 34 ft. fifth wheel weighing 11000 lbs. Best I have ever done was 9.5 mpg towing and around 18 not towing.

We have an 05 3500 2wd crew cab and tow a 35 ft alpenlite for a total weight of 22920 lbs and never have been below 10 mpg using math.
chevman

[Beaker]

We have a 2008 2500HD Duramax CrewCab long bed towing an 8000 lb TT. I carefully measured fuel consumption on a round trip from Baltimore to DisneyWorld down route 95 (very flat, about 2/3 of the trip at 65 mph, the rest at 55-60 mph). We got almost exactly 11.0 mpg average over the entire trip (close to 1900 miles)

About the same as mine. I get18-19 empty hwy.

Do you just hate these fuel-guzzling DPF trucks?!!

[debndave]

My father in law has the 2003 Duramax/Allison set up. 2 wheel drive, crewcab. He has a light foot at 73 years old and tells me that he gets around 12-13mpg with a 8700 lb (dry weight) 5th wheel.

[houstown]

Have a 3500 DRW Duramax that tows a 34 ft. fifth wheel weighing 11000 lbs. Best I have ever done was 9.5 mpg towing and around 18 not towing.