Last post on Dec 15, 2012 at 3:45 PM
You are in the Chevrolet Silverado & GMC Sierra
What is this discussion about?
Chevrolet Silverado 2500HD, Chevrolet Silverado 3500, GMC Sierra 2500HD, GMC Sierra 3500, Diesel, Fuel Efficiency (MPG), Truck
#617 of 620 Re: DURAMAX FUEL MILEAGE [exrench]
Dec 09, 2012 (10:27 pm)
I think you are going to be upset because I have a 2007 3500 dually with 373 gears in rear end it got 12.5 to 13.5 towing a 46 ft. gooseneck with living quarters and a race car which weighed about 16000 lbs that was new when it was at that and the older and more miles I put on it it got a lot worse I pulled a 2200 lb boat at 75 mpg from fla to sc last week and got 10.4 mpg so any body tells you they have to get broke in is blowing smoke because mine has 99689 miles on it and shows no codes or evidence of any thing being wrong I wish somebody had an answer because gm sure as hell don't and does not really care I bought this truck and it was supposed to be the best thing on the market but I surely have a different opinion about that and it seams nobody else has an answer either good luck
#618 of 620 Re: 2009 Duramax 2500 [kacansas06]
Dec 10, 2012 (7:02 am)
I have the same story with my 06Chevy 2500 diesel. Slow down , IT really does improve mileage.
#619 of 620 Re: DURAMAX FUEL MILEAGE [blackmax]
Dec 15, 2012 (11:13 am)
The toneau cover actually reduced your gas mileage. Myth busters on the discovery channel actually showed how a mini vortex make circles in the open bed of a truck with the tail gate UP actually has better aerodynamics than either a tailgate left down or a cover. Look it up.
#620 of 620 Re: DURAMAX FUEL MILEAGE [joemagic]
Dec 15, 2012 (3:45 pm)
You are correct. All one has to do is watch those covers as they go down a highway alongside your truck, always having ripples and bulges in it and it gets worse as you go faster. I think in that Myth busters the only thing they found that increased mileage on a bed was a full topper but it had to be the correct shape, I think made out of fiberglass. The metal ones don't help. My hard fiberglass deck lid which is not high enough to reduce drag actually lowered my mileage by around 1.5-2mpg.