2000 w900, 4.5 mpg ???

I drove a 2000 379 Pete for a friend of mine and I tracked every tank. The lowest was 3.87mpg and the best was about 5.5mpg. It was a 3406E 2ws with the 550hp file on it. Loaded was usually between 80k and 90k depending how much ice and snow I picked up a long the way. Also I would idle when it was below 0 degrees or when I parked in remote areas.

 

I have a 2003 Pete 379. Cat C-15 6nz 550 hp ( was 475 hp. Had it reprogrammed at Cat shop to 550 hp).
I was running NC to CA to NC. gross weight 55000-77000. Averaged 6.5 mpg running about 60 mph.
I let the rpm get down to 1200 before downshifting and never above 1500 rpm.

My Cat manual says run engine in 1200-1600 rpm range for best mpg. With a Cat, low rpm seems best.

I was pulling a dry van with no added aerodynamic equipment. Small fairing on sleeper roof.

 

i had a 99 star C15 475hp 18 speed with 355 and 1450 /1500rmp it ran great ,get out of the fuel pedal should get better . never seen a Cat that like high RPMS ,