Adding ATF to Oil before change

I was reading on reddit about people adding a bit of ATF to their oil shortly before doing an oil change. This is supposed to clear out gunk stuck in the engine.

 

Has anyone done this with these cars? Good idea or not so much?

I have heard about it years ago...many years ago.

 

I've always used Gunk Motor Flush when I felt the need to do that.

Very old trick but it still works. ATF is very high detergent and if you put about half a quart in and drive the car for 40-50 miles it will definitely loosen up some stuff, BUT if your engine is full of heavy sludge, it can also clog up an oil pickup, so be careful.

I would find it highly unlikely you have sludge in your engine if you have been doing regular maintenance.

I would find it highly unlikely you have sludge in your engine if you have been doing regular maintenance.

 

It was a trick for the old 283 Chevy engines and 289 Fords and Chrysler Leaning Tower of Power Slant 6's that would run too long without oil changes and sludge up with the old style motor oils. It works well, but again, it can actually knock chunks loose (if you have chunks inside your oil galleries...LOL)

 

Also used to pour ATF down carburetor throat if there was a stuck valve and it would sometimes actually knock it loose. Used water too to help burn carbon deposits that would get stuck on the face of a valve and not let it close all the way.

So, is Marvel Mystery oil ATF then?

Yea ^^^

I've taken a 100k mile engine apart and pulled the pan on mine around the same. Neither had any signs of sludge. If you've been doing regular maintenance, I wouldn't be surprised if it was clean.

Used water too to help burn carbon deposits that would get stuck on the face of a valve and not let it close all the way.

 

^ O yea, I still use that one. As you have seen a engine with internal coolant leak shows you how well "water" cleans, basically like a steam engine . Mix water and top engine clean together and its a party

So, is Marvel Mystery oil ATF then?

 

No...it's a top oil that has some weird stuff in it. The mystery is that you can put Marvel Mystery Oil in the oil and in the gas but....how does it know?

 

Read a Ferrari service manual and they state to put 1/2 cup of Marvel Mystery Oil in every tank of fuel because of the top oil keeps their valves lubricated and clean. The only reason I know this is because I used to rep Marvel Mystery Oil a number of years ago and I had a buddy that had a Ferrari 380 Spyder and he had me pick up some dented defect cans for him to use.

 

I would suspect it certainly wouldn't hurt an LGT either.