Fuel Quality

[Broompilot]

OK here it goes Petro fuel and others ran into a very smart Expediter yesterday in Cambridge OH. Followed him home into the Carolinas talked via CB entire time. He states that there fuel is junk, he uses the number of 45 or higher Wilco in Wythville VA says he gets 1 almost 2 mph better with the higher grade of fuel.

Now I filled up prior to Cambridge in Youngstown Oh drove in the snowstorm to Toledo pu a load and drove 70 miles East of Toronto in the storm back thru Columbus and over to 77. (roads were terrible so got on I70) My mileage was awfull not even 7. So I decided to stop in Wythville with him and topped both tanks off. Fuel increased to 9.7 mpg, now heres what I do not understand I kept the throttle down on every mountain, (up hill) Xmas eve wanted to get home I drove much faster keeping up with him than I normally do.

Heres my true question why when averaging 65 to 70 did it increase so much did the poor road conditions really play that much difference. I am at a loss to the mountians of WV and I got that good of mph with that high of speed up hills? And does anyone notice an increase in a 45 plus diesel.

I really thought that the biggest killer of fuel mileage was speed.

 

[RichM]

What seems to affect me the most is wind,then speed.

 

[Weave]

Just a wild guess here. When in the bad weather with the engine not running in the most efficient part of its powerband and the truck upshifing and downshifting a lot, the MPG was down. When allowed to get back up to speed in top gear with the engine running at a stable RPM in the sweet spot of its powerband, the MPG increased to its max. It takes the least amount of fuel to keep a truck cruising at a steady speed. The most to get it moving up to speed. By constantly speeding up and slowing down, the truck ran at its worst MPG. Most modern diesels are most efficient in the top 3/4 of their governed speed. Then when hammered down beyond that, the MPG goes down again.
Anyone confused? Me too
Merry Christmas,
Weave

 

[Broompilot]

Wind was very bad, average wind speed was 60km or 38mph that was not the gust but the steady wind forgot about that plus you are right averaged 25 35 mph for 14 hours closed the 401 and had to drive down a goat path for 200km. The only bright spot was I was not one of the poor trucks in the snow bank or stuck in the rest area and had fueled up knowing a storm was lurking. Thanks for your advice.