I have a 95 F-250 PSD 145k, I will have to say that I am always skeptical about putting any additive in to an engine except what it is intended for. I understood the concept of the 2 stroke oil and of course when mixed properly I knew it couldn't do any harm so after some research I tried it, and I have to say I am impressed, the engine did quite down a noticeable amount. It also was lobing a little at idle and that seem to smooth over. Now I don't know about fuel mileage b/c I always have different size loads behind the truck.
I mixed 1 oz per gallon, as I have seen others post.
Another reason this caught my eye is b/c we have a 91 roll back with the 7.3 non turbo, and a couple months after they introduced this ULSD, the injector pump went out while riding down the road. I don't know if it was coincidence but it happened and cost $650 to get rebuilt, plus there where 2 cars on the back of the truck, so it was quite an inconvenience. If a few dollars in 2 stroke oil can prevent this then I am happy to run it.