Oct 24, 2025 · Nobody knows what’s in it. It’s a mystery! I have used it, just to add a little something to an oil change. The synthetic aspect is surely excellent.

Feb 7, 2022 · Marvel Mystery Oil - Jack of all trades, master of none. But still a lot better than a master of one. Here are my uses in last 10 years across multiple vehicles and other …

Jul 7, 2008 · So what is MMO ? I have never used it, and I do not see any need for it in my personal fleet. It can go in oil, it can go in the fuel tank as well, so my thought is that at best its …

Feb 19, 2019 · Is it worth adding marvel mystery oil to my fuel tank every other fill up or so as a schedule maintenance plan? I have no fuel problems I'm just wondering if it's worth it to …

Mar 17, 2008 · Similar threads Thoughts on Using Sta-bil and Marvel Mystery Oil In EVERY tank of gas?

Marvel Mystery Oil? Lately I'm hearing some remarkable things about Marvel Mystery Oil used as a fuel additive in aircraft, from a VERY experienced and competent mechanic and aircraft …

Jan 16, 2006 · I have experimented with back-to-back runs of Rotella T Synthetic 5w40 with and without 20% Marvel Mystery Oil in my 2003 Cadillac Deville with a Northstar 4.6L engine. I …

Jun 30, 2011 · I'm now using Marvel Mystery Oil in the gas, carefully mixed at 4 oz per 10 gallons. Now here's the test I conducted. About the time I got my Jeep 4 months ago I became …

Mar 30, 2020 · This oil was very useful in older aircraft engines to scavenge lead deposits. While dibromoethane was added to leaded gas to do the same, some lead oxide did stay in the …

Jul 15, 2009 · What does Marvel Mystery Oil do? How does it work? What are any down-sides to it? I've got a mid-1950s engine that had stuck piston rings, smoked like a mosquito truck. I …