Originally Posted By: edvanp
I recently added 1oz of 2 stroke oil per 5 gallons of gas in the 4 vehicles I own (02 530i, 99 Jeep Cherokee, 09 Outback and 02 Bravada). The "butt dyno" noticed quieter operation and easier startup. The only one I'm tracking gas mileage on right now is the Bravada which is up slightly. I've used MMO on/off throughout the years and as an earlier poster mentioned, too much of it and I noticed a drop in mileage and I think performance. I'll continue to run this for another month or so and track mileage/performance.
You will see a drop in power and a loss of mpg with an OD of MMO. The same is true with TCW3, however an OD of TCW3 is more likely to foul plugs than MMO is. Mixing the two is a nice combo, or using either product as a stand alone works well too. In an older tired engine TCW3 works very well, I believe it makes for a better ring seal than MMO which is why so many people claim they feel an improved idle and a bit more power. Sorry its anecdotal I haven't run any scientific testing, and to tell you the truth I really wouldn't care what the results would be. There are enough people having positive experiences to make it worth trying.