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SH's avatar
SH
Explorer
Mar 05, 2015

Marvel Mystery Oil

Any one ever add this to fuel in your diesel trucks?

The only reason I ask is my 07 Duramax developed a light surging at idle. Researching the issue it is a fairly common problem especially with trucks using low sulphur fuel. The Fuel Pressure Regulator is the culprit. Keep in mind I know nothing about diesel engines but I found a home remedy for this exact (surging) problem. The fix says to drop a quart of two-cycle oil in the fuel tank to help lubricate the regulator.

So I tried it and the problem (surging) immediately went away! Not sure if it is a permanent fix but service center said changing the regulator is a $1000+ job!

I have used Marvel Mystery Oil for years in my motorcycles but never thought about putting in my diesel fuel every so often. I used a regular two-stroke oil this time but would consider the Marvel in the future.

Any thoughts?

20 Replies

  • When I had my 05 duramax, I always added a quart of 2 stroke oil on every fill up. Truck ran much smoother and was more quiet. Never had any issues. I would not, however, use it on the newer diesels with the DPF.
  • Hi. Be careful of what may of may come out of the tail pipe.
  • Turtle n Peeps wrote:
    Any thoughts?


    Ya, don't put things in your late model truck fuel tank that doesn't belong there.

    What MMO can't do for you.


    Actually I frequent the Diesel Place as well...that's where I got the Fuel Pressure Regulator information and the suggestions to use two-stroke oil! The study does say MMO may damage newer diesel engines!
  • My owner's manual for my new 2015 Chevy Impala (3.6 V6), says not to put anything in the engine, other than those lubricants indicated by GM.

    Think it would be the same for the truck line.
  • I don't know what MMO is Scott. That's why I asked about it. Could be a kerosene base for all I know! I will leave it in the motorcycle!

    Thanks!
  • Lubrication is such a big deal in our engines that I would not chance putting something like that through the fuel system. And isn't MMO mostly kerosene or some other kind of solvent? That would be murder to some of the close tolerance parts I would think.