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
#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.