These are tabs that you stick on your cab extender farings - right along the edge. You can only put on so many. They have to be spaced according to their template.

thanks. that tells the story.

Yeah,it sure does if I only pulled 25k and ran 60mph I could get 7mpg with my stupid Cat.

not cutting you down,you just have abnormal circumstances

Still, I know guys with classic trucks that can't even get 6 mpg running from Winnipeg to Minneapolis. Maybe a touch faster(62 mph), same weight.

I avg 6mpg pulling maxed out tankers,running 65-70 on the east coast,guess those acert engines aren't all bad.

Yeah those tankers must go through the wind pretty easy compared to our big boxes.

Yeah but 45k in a tanker feels like 100k in a box,they are defintely hard to get going and hard to stop.

That's true, especially those unbaffled ones.

Wouldn't want to ever drive one when it's slick out. Must be fun!

i get 7 mpg doing 60 pulling 48.000 one way & deadhead back. in a cabover 11.1 det 350 horses.

Allan,

What impact do you think just tractor aerodynamics have when pulling a tank? Also, don't remember where I got this link from, but here's some interesting reading about fuel mileage from Cummins>

http://www.everytime.cummins.com/eve...Whitepaper.pdf