The theory behind 2 stroke oil is lubricity and low-ash. While it should certainly perform this task fine, it will add little in terms of cetane boost, cleanliness, and water control. I would add it at a rate of say 1:100 or 1:50 at most for lubricity. If 2 stroke oil can adequately lubricate an engine running at high rpms, it certainly can add some much needed lubricity for our diesel fuel systems. However I feel there are better choices that add more benefits while still having those that 2 stroke oil provides. Any good diesel additive like PS Diesel Kleen, Cen-Pe-Co, Schaeffer's, Amsoil, Stanadyne, Howes, etc. will not only lubricate, but add cetane, clean, start easier, control water and algae to some extent, and improve combustion. I have a 2004.5 Dodge w/ Cummins but am currently experimenting with several adds in my wife's 01 Jetta TDI. I have been using Cen-Pe-Co Diesel Klenz at the maintenance rate of 5 oz., and also combining the Diesel Klenz with about 6 oz. of Neutra per tank. I have not seen much economy increase with the mixture, but there is definitely an increase with one or the other alone. I got a quart of Lucas UCL tonight and am going to throw that in the mix with the Cen-Pe-Co and Neutra at recommended rates and see what happens. I am not going to put all 3 together, I will try Lucas with each of the other two.
There is ample evidence that suggests that the typical diesel fuel adds such as Howes, Power Service, etc. that have that distictive smell will lead to increased wear metals during the course of an oil change interval. This is exacerbated during cold weather as more fuel slips by the rings and ends up in the oil. Thus the reason I am experimenting with 2 proven non-wear metal increasers in Neutra and Lucas to see if I can duplicate the mileage impact I have seen with the "stinky" adds. I have been recording the data, I believe it will be good data since nearly all her miles are similar in nature and she always fills up at the same place. She has new tires, an alignment, new air filter, fuel filter, etc. to throw some of those things out. I will start a post once I can draw some conclusions that hopefully can help some people out on this stuff. Best of luck, and try to stay away from overdosing on "stinky" adds as that definitely seems to be the recipe for increased wear metals.
