[Night_Sailor]

Originally Posted by jray3

The OptiLube XPD that Night Sailor endorsed is about 90% naptha and trimethylbenzene. On Amazon, paint-thinning Naptha is $11/quart ($44/gallon) and Opti-Lube XPD is $14/quart, so just a 27% premium for the 10% of trace ingredients. (Plus pricey shipping) Trimethylbenzene is nasty stuff that's hard to buy, so it sounds worth a try from a local retailer rather than just pouring in a can o solvent, and even a 5% increase in fuel economy would be worthwhile for something that adds 11 cents per gallon (2.75%) to $4 diesel.
http://opti-lube.com/downloads/MSDS/...I_XPD_MSDS.pdf

A 5% fuel economy improvement on $4 diesel would breakeven at $25.60 per quart of additive, if used to treat 128 gallons, as claimed. Pennies, but worthwhile especially if the other benefits of fuel system cleaning and lubricity are realized...

Naptha would not add any lubricity.

This additive does improve lubricity. I noticed almost immediately that the engine ran quieter. It was like a sprinter taking off a heavy back pack.

I did run a few tanks with 2 cycle oil when I ran out of Optilube. It seems to work fine. My best tank with the camper on was on 2 cycle additive--this was in the flats of Florida--which I'm sure helped a lot.