Marvel Mystery Oil (MMO)

my father-in-law uses this stuff religiously, ive used it in 1 of my older cars about a year ago. im about to roll over 200k on the taco, & ive been thinking today about starting to use it in the taco. does anyone here use it too, or has used it in the past? if so, what were/are ur thoughts on it? thanks in advance!

 

after a little digging....from a ca. university study. I've never used any additive, simply keeping the oil changed always worked for me. However i have seen people use some additives and stuff went bad shortly afterwards.

Detergents And Solvents
Many of the older, better-known oil treatments on the market do
not make claims nearly so lavish as the new upstarts. Old standbys
like Bardahl, Rislone and Marvel Mystery Oil, instead offer things
like "quieter lifters," "reduced oil burning" and a "cleaner
engine."
Most of these products are made up of solvents and detergents
designed to dissolve sludge and carbon deposits inside your engine so
they can be flushed or burned out. Wynn's Friction Proofing Oil, for
example, is 83 percent kerosene. Other brands use naphthalene,
xylene, acetone and isopropanol. Usually, these ingredients will be
found in a base of standard mineral oil.
In general, these products are designed to do just the opposite
of what the PTFE and zinc phosphate additives claim to do. Instead of
leaving behind a "coating" or a "plating" on your engine surfaces,
they are designed to strip away such things.
All of these products will strip sludge and deposits out and
clean up your engine, particularly if it is an older, abused one. The
problem is, unless you have some way of determining just how much is
needed to remove your deposits without going any further, such
solvents also can strip away the boundary lubrication layer provided
by your oil. Overuse of solvents is an easy trap to fall into, and
one which can promote harmful metal-to-metal contact within your
engine.
As a general rule of thumb these products had their place and
were at least moderately useful on older automobile and motorcycle
engines of the Fifties and Sixties, but are basically unneeded on the
more efficient engine designs of the past two decades.

 

thank u for ur input, that was very helpful!

 

I've used it, 1 -2 drops, to keep the air tools in good condition; air drill, sander, impact
and as a cleaner, but never as an additive in the cars

 

I use MMO in my Cub Cadet Garden Tractors, 2oz in 5 gal gas prevents valve sticking, adds a tiny bit of lube to the top end, Seems to reduce carbon buildup in the combustion chamber. I plan to do the dreaded MMO piston soak on my oil eating 01 Saturn. Im going to load up the crankcase as well. It is claimed stuck rings is the problem

 

I have used MM oil in several older vehicles and never had any ill effects, but can't cite any direct benefits either. I always keep up on maintenance so I can't say if it helped anything or not. It supposedly helps maintain a strong oil film (shearing protection) and prevents sludge and varnish, which is why I used it. I pulled the head on my 65 mustang 6-cyl and it still had the cross-hatches and a superfine polish on the surface of the cylinders and I was using MM in that one, about 6-8 oz per 5qt. But again they might be there without the MM too. I have not put anything in the Tacoma crankcase other than straight 5w-30... now the MM only goes in the 4-stroke off-road bikes, 2oz per 5 gal. Sorry I can't be more helpful but wanted to chime in with my experience.