Just an update. I tried some Hot Shots Diesel Extreme fuel system cleaner. I ran it thru consecutive tanks putting 8ox per fill-up as instructed. The first tank was used up mostly towing to the track so the tank only lasted about 250 miles and performed a regen while towing. The next week I took a 1000 mile trip to North Carolina, I again put in 8oz of Diesel Extreme in the tank before the trip (this is 2 consecutive fill-up's with the cleaner). Same fuel economy as usual, about 32 MPG. I still performed a regen on the way back at an interval of about 550 miles so no change. At this point I was thinking "snake oil". This is where it gets interesting. I've since done pretty much only local driving in the past 1500 miles since my trip to NC in November. I have been using 2 oz. of Hot Shots Everyday Diesel Treatment (EDT) every fill-up instead of my usual Standyne. My regen interval with local driving after the Diesel Extreme treatment has increased to about 300 miles, I'm ecstatic as the interval has at least doubled. I still cannot conclude if its the EDT vs. Standyne or that the Diesel Extreme cleaner cleaned the DPF really well. I previously have taken the truck on long 500-1000 mile trips where it performed a regen on the highway so it was not just the NC trip that did it. My increase in regen interval came after the NC trip using Diesel Extreme cleaner. What I haven't yet concluded is if it's the continued use of EDT vs. Standyne that has kept the regen interval up for the past 1500 miles. I plan to switch back to Standyne in another fill up or two to see if my regen interval stays at 300 miles locally or if I need to switch back to EDT. One thing I do plan to do is I am going to use Diesel Extreme cleaner every 5000 miles when I change oil. There's no doubt in my mind that the cleaner did something. I still need to conclude if the Standyne is resulting in poorer regen intervals. After the NC trip using diesel extreme I have noticed that my DPF percentage reads very low after a local driving regen now, starting at like 4%. Like now the regen is doing a more complete job of burning the soot out of the DPF. Previously regens preformed during local driving would drop the DPF soot percentage to only about 12-16% and it would fill up rather quickly over the next 130-150 miles. I now notice the soot percentage filling up at a much slower rate. Currently I've gone 170 miles since last regen and my DPF is at 47% with local driving. Previously even highway regens would drop the soot percentage to only about 9%, now local is even lower that previous highway.
You may ask why I don't just stick with EDT and ditch the Standyne. When I use Standyne I'm putting in a mixture of Standyne Performance and Lubricity formula. After owning a GM 6.5 diesel I'm always extremely concerned with fuel lubricity or the lack there of with ULSD. The IP on the 6.5 was extremely sensitive to fuel lubricity and most IP failures occurred due to poor lubricity to the tune of a $2500 pump. I ask myself how much fuel lubricity can be added with only an ounce or two of Everyday Diesel Treatment? Currently I'm putting 5 oz of Standyne mixture per fill-up. Basically the recommended Standyne treatment of Lubricity and Performence per 20 gallon fillup which is 3oz Performence and 2oz Lubricity.