2001 GMC 2500HD Duramax / Auto Allison tranny.
Before the diesel fuel change from the low sulfur (500ppm) to the Ultra low sulfur (15ppm), I got what I thought was very good mileage. Empty, I averaged over 21mpg per tank and just barely under 20 while pulling 2000lb rig. Didn’t matter much about conditions or too many other factors. Was very consistent.
After the change to the B.S. Diesel fuel the socialist burro rats of America forced upon me, I suffered a dramatic drop. I average about 17 empty and I just want to put the blindfold on when I pull my boat. That’s over a 20% drop in efficiency or an increase of 20% increase of fuel purchased at an ever-increasing price. I have run all the different sulfur additives and a few of the homemade additive formulas that were supposed to be the cure for the drop with the new diesel fuel formulas. I only saw up to an 8% increase in mileage and in some cases, more than 25% increase in cost for them.
I know a couple of guys that make their own bio-diesel. If I understood them correctly, it costs them about 80 cents per gross gallon to make and their mileage pulling a boat stinks. So, I guess until we are on the board of directors at Exxon and Mobile, we get to use re-formulated fuels that lack the gusto to give us decent mileage and we get to buy more of it…..