mine also seems quieter on ulsd . and way way less smoke and i cant tell any diffrence in fuel milage on the 01 pulling or empty. i realy like the less smoke part
Hey go to Wal Mart and read the back of Marvels Mystery Oil and read the back of the Gallon or quart "I" buy the gallon for $12, but it reads in big bold letters DOES NOT COMPLY WITH FEDERAL ULTRA LOW SULFER CONTENT REQUIREMENTS FOR USE IN MODEL YEARS 2007 AND NEWER DIESEL MOTORS AND ON AND ON... That's what my dad and I have been running. My dad has a 03 7. 3 and around here this ultra low sulfer has been killing the ol' fords, but my dad's has been doing good...
I've been adding 2 cycle oil since 2001. Much cheaper than other additives and 2 cycle is 99. 9% ash free.
I use China-Mart brand 2 cycle oil and mix at 200:1. 2 cycle oil is designed to be burned inside the engine.
When I change my transmission oil (Royal Purple SynchroMax in the 5600) I use it instead of 2 cycle oil.