My only rule is that I don't fill up at the podunk stations that are known for selling cheap gas. :wink:
I ran Diesel Kleen in a few tanks of mine. Didn't notice any changes at all in mileage, start up, power, etc. Switched to a 1:128 ratio of 2 stroke oil (1oz per every gallon of fuel). Truck is much quieter, runs smoother, and I get better mileage. Plus, it adds lubrication that the ULSD has taken away from our trucks.Why 2 stroke over Diesel Kleen?