We have seen quite a few additives come down the pike over the last 30 years.  "Slick 50"; STP; "Tuffoil"; Rislone; Motor Honey; Restore for the oil systems.  Lucas and others for the tranny; Blue Devil, Barsleak and others for the water system; "Platinum Fuelsaver" and other contraptions as add ons for the air intake for better mpg.  

 

Which of them have some merit and which did real damage?/

Trans-X works great on 99 & 00 Leggies with delayed forward tranny engagement problems. Not aware of it having any benefit for any other applications. Unaware that the product has caused any problems.

no additive can 'repair' something broken, but there are a few I have or would use under certain circumstances;

 

Subaru Coolant Conditioner

 

Trans-X

 

Techron

 

SeaFoam

 

HEET

 

Stabil

Edited July 31, 201510 yr by 1 Lucky Texan

there's only one necessary one, Subaru requires the Coolant conditioner in Phase II EJ25's and it helps mitigate external coolant leaks that sometimes happen in EZ engines as well.

 

otherwise, entertain them only if you're addressing an issue.

Seafoam!

Don't know how many idle problems I've fixed with Seafoam. I usually use about half a can in the intake and pour the other half in the fuel tank. The stuff just works.

Last time I seafoamed my car one of my newer neighbors down the street thought it was on fire! The wind had shifted and blew all the exhaust back under the car and it was pouring out of the wheel wells and all under the hood and coming out of the grille.

So much fun!

~► http://www.ultimatesubaru.org/forum/topic/66817-lubricants-additives-myths-reality/

berrymans b12 chemtool, it comes in a can that looks just like a seafoam can and works just as good for half the price. i use it all the time, a triple does will do wonders for a clogged carburetor  

I used Lucasfuel Fuel Treatment before I changed my fuel injectors and it seemed to make enough difference in mileage (~2mpg) that I continued using it.  My car is old enough (+200k) that it may not be the best to test. Pretty cheap at the blue box with smiley faces.

 

::shrugs::

"Restore" seems to be a popular product.  I wonder what ever happened to Slick 50?

I used restore on a 1979 Dodge slant six that would smoke on start up. Within  100 miles it stopped smoking.

Check out the forums at Bobistheoilguy.com.  They love this kind of auto-nerdism and there are several chemical engineers who roam the forums.

my general take on most additive products - if it sounds to good to be true, it probably is a bunch of marketing hooey.

 

that said, products that I have used successfully:

Seafoam - for multiple purposes

Trans-X - in an 89 Ford Taurus with tranny engagement issues

Berryman's B12 - specifically for cleaning carbs/carb parts - on both an old Ford truck and motorcycles

 

I try to stay away from things like the stop-leak stuff as they are known to plug up small passages.

Oil additives - eh - most are marketing hype garbage. Regular oil/filter changes will do more for your engine than any of the additives will.

 

And Slick 50 is still around, just without all the hype after an FTC filing alleging false advertising (filed in 1996):

https://www.ftc.gov/news-events/press-releases/1996/07/quaker-state-ads-slick-50-are-false-and-misleading-ftc-charges

I did not see Marvel Mystery Oil (MMO).  I had a non Subaru with a noisy lifter years ago, added half a quart of MMO. still noisy, added the other half quart, noise gone forever.  I have added it to all my small engines gas all my life now.

I did not see Marvel Mystery Oil (MMO).  I had a non Subaru with a noisy lifter years ago, added half a quart of MMO. still noisy, added the other half quart, noise gone forever.  I have added it to all my small engines gas all my life now.

+1 vote for MMO. Yea, I forgot about that product too. Good stuff, been around for years. I recommend it.

What's in it?  It smells like petroleum distillate....  Plus red dye.

 

Too bad all these companies have their confidentiality rules so you can never find out what is in the product.

occasionally you CAN find info on components of stuff. Either someone has analyzed it or there's 'just' enough info on the MSDS to figure it out.
 
a quick search finds that wikipedial thinks it is about 74% 'mineral oil', 25% Stoddard Solvent and 1% lard.
 
the MSDS somewhat confirms the 2 major ingredients; http://www.turtlewax.com/res/msds/MM010-4.pdf
 
more reading;http://bbs.zuwharrie.com/content?topic=39758.0

 

(doubtful that anything at the 1% level is particularly active in the substance but......?)

 

Stoddard Solvent is (or 'was' company claims they use something 'similar' now) about 1/2 ingredients in WD-40 by the way. (it's sorta like a deodorized kerosene)

Edited August 5, 201510 yr by 1 Lucky Texan

Does paint protection products count as a additive?  You are adding it over your paint.  If so, I tried the new Meguires Ultimate Wax on my car last November and the water is still beading.  You do need to use the Ultimate Polish first as it is not a one step cleaner wax.

 

Never found a oil additive that was worth anything, most end up doing harm.  An oil change is often all that is needed.  I have used alumaseal for a cracked block (cast iron) and it worked, but it never worked on a leaking radiator, water pump, head gasket leak or cracked aluminum head.

 

I used Slick 50 for manual transmissions in my Nissan Pick Up.  I put it in at around 20k miles along with Mobil One 75w90 gear oil.  At 180k, I checked the transmission and found it completely dry.  I don't know how long it was dry but it took the full 2.1 qts to fill it back up.  At 195k, it is still full, go figure.  No damage to the transmission either.

 

Flush chemicals for cooling systems have always damaged by cooling systems.  Every time I used one, it ate every seal and hose in my cooling system.  When this happened on a car that had all new hoses in the last two months, I finally got the connection.  I never had a problem with a cooling system until I flushed it, then I always had problems for awhile.  Now I do a simple drain and fill every 5 years or so (more often "or so") and I don't have problems.

 

I hear that Trans-X works on automatic transmissions but I haven't used it myself.