Join Date: Nov 2007
Location: College Station Texas
Re: Effect of ULSD fuel on Mileage???
I noticed a drop in mileage after the implementation of the ULSD. Pre-ULSD I was able to get about 19 mpg
on the highway with a stock truck, now after ULSD and all the mods in the sig, I can only get in the low 18's, so it definately lowers the mileage. When the sulfur is removed, the energy content that is in sulfur is also removed, so now there is less energy per unit of fuel than before, that is why the mileage will go down with the ULSD. I am not a mechanical engineer, but I did have one thermodynamic class, and it all has to do with energy, and entropy, and blah blah blah...Basically there is just less juice in the diesel now.
2003 7.3 XLT FX4, AFE Stage 2, Regulated Return, Bowl Delete, 3/8" line from tank to heads, Pre/Post Filters, Tank mods, DP F5: 60T, 80E, 120R, 6.0 IC, 6.0 Trans Cooler, Suncoast Shift Kit, Wicked Wheel, ITP Boost Annihilator, Di Procol Optix, Straight Pipe, CCV, 285/75/16 BFG AT's