how fast do you drive

Nowadays I just do what ever the speed limit says or what ever the sixty some mile an hour truck is doing in the middle lane on the three lane road is doing because he does not want to have to slow down so I have to .

 

When going ''home''...Hammer Down 80 MPH,left lane all the way...

 

I don't put a whole lot of belief in an engines "sweet spot" unless you want to run as fast as you can before the fuel mileage starts to dramatically drop. My trucks sweet spot is 1325rpm at 65mph, but I have been running 60mph for the last month at 1225rpm, and getting better fuel mileage.

 

set the cruise st 62 or 63 and getting 7.0 with a c15

 

Huh? What part of pushing more air out of the way at a higher speed does not have an effect on the fuel mileage? You say wind has an effect, but pushing more air at a faster speed doesn't? Been a long day, I guess. Just couldn't get a grasp on that one.

 

You the man! I am running about 60-62 and my last 3 fills were 7.8, 7.7, and 7.9 respectively toting an average of 35,000 lb.

 

70-75 and avg 4-5 MPG depending on load

 

I understand. Let me try to explain. The most detrimental wind is not a direct headwind, but rather a ''quartering'' headwind blowing at about 45 degrees to the trucks path and the most beneficial wind would not be a direct tailwind but a ''quartering'' tailwind of about 30 degrees from the rear. This is why I say that wind is more of a factor than the speed of the truck.

 

Like I told my ex wife, I never drive faster than I can see, besides its all in the reflexes. ~ Jack Burton

Seriously:
65 most of the time
6.34 2012 average
5.89 first quarter 2013
Mercedes putting 404 HP on the ground @ 1600 RPM pulling a 48' flat

 

A fast 57 mph and I HATE IT.But if I was an O/O with the price of fuel I would probably drive between 60 and 65 with the cruise set.