Miles per gallon with your Chevy/GMC Duramax 6.6.

My 2008 Chevy duramax diesel gets approx 10.8 mpg when traveling at 65 mph.

07 2500 D/A and get between 10-12 towing at 62-65 MPH. Unless I am pulling a hill, mine stays about 1500 RPM cruising at 60 MPH.

MMurley said:

Bout the same as mine, then. Do you notice a difference with the k&n?

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It was noticeable. I removed it one trip to see and I did notice the difference in power. It could have been other variables (ie. Weather) but the filter is what I blame.

I have an o6 duramax and get about what everyone else is gettin about 17mpg around town 20 or so on the highway and between 10 and 12 towing. the truck has 44,000 miles on it. give it a little time . I also cruise at about 55 to 60 mph

I have an 09 Chevy diesel 3500 with drw and i sure wish i could get 11 or 12 MPG with it ! I get about 8 when pulling the 3912 Cyclone ! That's going 64 or 65 !
chaseb

1231ChaseB said:

I have an 09 Chevy diesel 3500 with drw and i sure wish i could get 11 or 12 MPG with it ! I get about 8 when pulling the 3912 Cyclone ! That's going 64 or 65 !
chaseb

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Looks like our rigs are about the same weight and with the same towing speed I also get about 8.

MMurley said:

Just joinedthis site today and I have a question for all you Chevy/GMC drivers outthere. I bought a new 3270RES two weeksago and this weekend took it on a 250 mile jaunt to check it out. I am pulling it with a short bed 2007 2500HD6.6, all stock. The trailers dry weightis just under 11K. It towed like adream. I haven't towed anything thisheavy with this truck before and was wondering what you 'all get for mileage. Around town I get about 17, on the road20-22. Towing the trailer I was gettingright at 8.6. Speed limit in Texas is 75where I was at so I set the cruse at 70 and it never budged off of that. Towing something that heavy and at that speedI assume that the 8.6mpg is about right. Anybody getting better? If so letme know (a possible excuse to get a new truck).

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There is a quirky law of physics that mentions that friction goes up by the square of speed. Head winds and tail winds have dramatic effect on mpg. Speed creates a significant head wind. So my advice is to slow down and enjoy life especially when fuel is as high priced as it is. I drive 62 mph and get 12.5 ave mpg over the last 1500 miles across while driving coast to coast. Most modern diesels do about the same. Oh yes, then there are the tires--