I have been using this product off and on for a few years, but I started using it on a daily basis a few months ago. It can be added to the gas and/or the oil. One thing I noticed is that my oil consumption has dropped. I did not have to add any oil for a month. The engine used to use maybe half a quart every two weeks, but now, the oil consumption is so minimal that I can top it off with MMO. Keep in mind the oil level was checked every week. Drivability has improved, and so has the fuel economy. When I am using the A/C, the fuel economy impact has been minimal. The engine is a little more responsive. I also noticed that the oil did not turn black, as it does when it is time for an oil change. The engine starts easier on a cold morning, is quieter, runs cleaner, and acceleration is smoother with less effort.
I also add it to the gas every time I fill the tank. The directions call for four ounces for every ten gallons. That means eight ounces for my seventeen gallon tank. There is a graduated scale on the bottle for easy reference. It is also great for lubricating the fuel pump, for those of us who live in a state where either E10 or E85 gasoline is used. I started using it on a daily basis is because alcohol is very corrosive to fuel system components, which probably contributed to a fuel pump failure last year whilst I was driving home from work.
Before you use it, follow the directions, and use your common sense. It is not meant to be used as a stand alone product in the engine. If you are a quart or more low on oil, add the amount of oil that is needed. But for the last pint, you can substitute MMO. Do not overfill. I just eyeball it, depending on the oil level. If you add it to the gas, again, use your common sense. Look up the fuel capacity of your car, and use the recommended amount of MMO.
Your experience may differ, depending on the kind of car you have, the engine, the viscosity and type of oil that the engine uses, your driving style, the gas you use, and the climate. I have a 2006 AWD Equinox with the V6 engine, a mix of highway and local driving using 87 octane E10. If you have a newer car, use Marvel Mystery Oil Ultimate. The Classic is for older cars like mine. If you have a diesel car, do not use this product because it can raise the sulfur content of the fuel, and possibly damage the emissions components. I would recommend using Hot Shot’s Secret Stiction Eliminator. MMO can be used in lawn mowers, garden tractors, and gardening tools that use a gas engine. Just follow the directions, and don’t go crazy with it.
Thanks for reading my review. More reviews are coming. Sat Nam.