Quote:
Originally Posted by Stretch56
I'am one that keeps the speed down, about 57, helps save the fuel.
|
But you're wasting fuel when towing with the OD turned off.
A coupla years ago I did a test. 8,000 pound 5er trailer plus 2,500 pound tag trailer, cruise control set at 62 MPH (1,800 RPM in OD, 2,350 RPM with OD locked out), calibrated speedo. Filled with fuel until liquid diesel at the cap. Towed 350 miles to Dallas going downhill with the wind behind me and with OD locked out. Filled to the cap again. Less than 10 MPG.
Towed 350 miles back home, up hill and with a headwind, same load and same 62 MPH, but used the overdrive everywhere except climbing Ranger Hill. Filled to the cap again to be certain my MPG calculations were good. Over 12 MPG.
So at least on that trip I got 20 percent better MPG using overdrive everywhere I could.
