It has to do with the expansion of the tefelon molecules that will actually plug up the oil filter and possibly other oiling port or at least reduce the effeciency of those ports over time. The stuff does work and does coat(remember, it coats!), but when those tefelon molecules change their form after they have been used for so long or under certain conditions, they will actually expand. Dupont actually has a technical note on this that suggests not using it in street driven vehicles for this reason. For race cars that change there oil every event it may be fine, but people that use there oil for 3-4 months sometime longer the molecules will expand and eventualy start gumming things up. Not sure if gumming is the right word, I am not expert, but I did read the document a couple of years ago. If I still have the actual info I will post it. Can't remember right off hand what I did with it.
I started putting Slick 50 in my Sentra at about 65K miles. When I sold the car at 175K miles (on the 3rd bottle of Slick 50) it still ran like new. Half that time it was in Montana, which meant in the winter it was started twice a day in sub-zero temperatures, and in the summer it spent most of the time sitting in the driveway while I rode a bike to work. It went up to 5 months without oil changes at times, and it went on numerous road trips in -20 degree weather and 110 degree weather.
I can't say whether the Slick 50 really made a difference but it sure as **** didn't kill the car!
Every 'scientific' article I've read on this stuff has been horribly biased for or against the stuff. It worked for me in that car.
No valid test (controlled conditions, front and back end testing) performed by competent, non manufacturer groups (university mechanical engineering depts., automotive testing labs)I have ever seen demonstrates any substantial benefit. I think the downside from using these products is limited as the manufacturers would naturally desire to limit their liability (like to buy a new Lexus motor?). Buy the proper weight SJ approved oil, a decent filter and replace them every 5K miles. Do this and you should have a long trouble free life from your Z motor they are really durable especially the bottom end. As much as the marketing departments of these companies want you to believe it - there is no "MAGIC" bullet for motor wear.
First of all it is "Teflon" which is the trade name that Dupont uses for polytetrafluoroethylene (PTFE). PTFE is inert to virtually all chemicals and is considered the most slippery material in existence, which is why it used to coat many things such as fabrics, pots and pans and its use in Slick 50.
I am not a Slick 50 supporter, however you are misled to believe that "when those tefelon molecules change their form after they have been used for so long or under certain conditions, they will actually expand". PTFE is chemically inert and physically one of the most stable polymers known to man. PTFE will NOT alter its chemical composition or its physical properties from use in an internal combustion engine. Here is another thing to keep in mind. I read once where it was stated that the PTFE particles would clog up the oil passages in an engine. Not true. Slick 50 says that the PTFE coats the internal engine parts. Not true.
Both of these statements are false merely because of the fact that once PTFE is formed it will not bond to anything. Period. They don’t spray PTFE onto pots and pans, it doesn't work that way. The idea that PTFE would help in an engine wasn't a bad idea, but for it to work they should coat the internal parts of the engine with PTFE prior to assembly, then it might do some good.
Personally, I would use a high quality synthetic (I use Mobil 1) and change the oil and filter frequently. I consider it to be cheap insurance.
It's true that once PTFE has been "created" it doesn't readily stick to anything, but it can be altered and made to stick to things. That's how they get it to stick to pots and pans. The PTFE in Slick 50 is a modified PTFE molecule, with a metal reactive tail added to it so that indeed it will bind to metal engine parts. That's why you only have to add Slick 50 every 50,000 miles, even though you may change your oil 16+ times over that 50,000.
I use a generic PTFE additive in my cars, but for me it's just a little extra piece of mind. I too think that your best bet is regular oil and filter changes.
well what ever is in the stuff it cant really be that great for your car engine. I mean really guys do you want to add something into your engine that says.....shake well then add to warm engine....just go synthetic its worth the extra money in the long run