Marvel Mystery oil is worse than adding nothing according to a lubricity test for injector wear.
17)Marvel Mystery Oil
Gas, oil and Diesel fuel additive (NOT ULSD compliant, may damage 2007 and newer systems)
HFRR 678, 42 microns worse than baseline fuel.
320:1 ratio
10.4 oz/tank
$3.22/tank
http://www.dieselplace.com/forum/76...28-lubricity-additive-study-results.html
