Originally Posted by Bruce B
Curious about your cruise control comment...
I can always out perform my cruise control by getting higher mileage numbers, mile after mile. I can anticipate hills, I can slow down when necessary and the difference is at least a mile per gallon better. Even over the long haul my numbers are better...
Again, just wondering
Call it "in the interest of science".
Over thousands of miles CC is superior. That any of us may turn it off in traffic, in the hills, etc. is beside the point. KENWORTH and the big diesel engine manufacturers -- in a business where they are interested in 100ths of a mpg -- have studied all of what goes into fuel economy. CC is better.
For comparative purposes, the use of CC takes away the irregular uneven driver patterns of throttle use. Yes, I "know" how to do it and understand the point made. But todays CC is a far cry from what we had in 1967
So, if I had this truck and was wishing to offer useful information I'd search out and correct all the mechanical relationships with the combined rig (not done 97% of the time), scale it carefully and use recommended tire pressures, and run at a speed below the point where air resistance takes off.
That way nearly anyone can duplicate the test. Correct for weight of the combined rig given the same trailer type. And the rest of us can help make guesses to provide a corrective factor for climate and terrain.
Probably most towing will be done in the warmest months. And a sufficient amount of non-mountainous travel will then "reveal" what can be said for the range of mpg seen by owners of this trailer brand under those stated conditons. Tom gets X and Mike gets Y and we can "see" the differences in combined rig weight plus colder/hotter and versus sea level or High Plains.
The end result would be the cents-per-mile calculation. When diesel is $3.50/gl it appears an EcoDiesel can tow one of our trailers for (fill in the blank) cents-per-mile fuel cost.
Likely that would be a few pennies difference between owners at most. Then the comparison to a gasser under otherwise similar conditions applies. A range, and then factoring the 30% premium diesel price.
The other uses of the truck (solo, city and highway, number of annual miles, empty or loaded, etc) make for undrstandable confusion on what it costs to operate.
My guess is that the ED pickup will be somewhat better versus a gasser in towing with the fuel price correction. But that it will shine for the driver who operates it solo with the goal of highest mpg on highway. That low annual towing miles versus high solo non-stop travel will be the "sweet spot" for owners.