I concur, Diesel Power magazine did a whole write up on fuel additives not too long ago. 2-stroke oil made a change, but nothing monumental. The biggest change was an actual no kidding fuel additive, can't remember the name. We're talking a 200:1 mix here also. So, on a 20 gallon fill, its about 13 oz. 128oz X 20=2560oz then divided by 200 is 12.8

 

WoW very interesting. I had no idea there was that in-depth study on ULSD. And I can’t believe what little lubrication we get for that. Anything is better than running nothing. Additives are the way to go. And used motor oil I never have heard of such a thing. but great article..

 

Found it!

Fuel Additive Test - Ultra-Low Sulfur Diesel - Diesel Power Magazine

In short:
NO ADDITIVE
Highway Average 14.6 mpg
City Average 13.7 mpg
Overall Average 14.1 mpg

TWO-STROKE PRE-MIX
Best Highway (one tank) 16.3 mpg
Best City (one tank) 14.9 mpg
Highway Average 15.6 mpg
City Average 14.6 mpg

OPTI-LUBE XPD
Best Highway (one tank) 17.4 mpg
Best City (one tank) 15.7 mpg
Highway Average 16.1 mpg
City Average 14.4 mpg

FPPF 8+ CETANE IMPROVER
Best Highway (one tank) 17.3 mpg
Best City (one tank) 15.0 mpg
Highway Average 16.1 mpg
City Average 14.9 mpg

 

this time of year with the winter blend mpgs go down. i am down about 2 mpg

 

Same here, I don't even bother checking it anymore. It's more of a toy than anything. I never calculated mileage out of my wheelers or my sleds, why should I care about this right?