I'm willing to bet that thread contains more useful information than this current thread will bring.
Originally Posted By: Road Rage
I searched my lube library (I am an ME and was a tribologist, currently IT Director for R&D at a Fortune 8 company). Here is what i found:
1) A US Army study of Slick-50 that found it did not do what it said, and actually increased wear in the cam lobes. It indicated the product should not be used in any internal combustion engines in the Army motor pool.
2) PTFE breaks down at high temps
3) PTFE can migrate under heat and pressure
4) PTFE is an effective dry lubricant and that is where it is best used, such as in space equipment and open gears/rollers
5) When burnt, it forms a corrosive and toxic product.
6) It is chemically inert and resists oil - why would you want that in most areas of an engine? It can be used on piston skirts, con rods, and rocker springs because it resists the accumulation of oil, which in a racing car has benefits, much along the lines of a windage tray.
7) There are no scientific studies I have seen that indicate PTFE colloids will "plate" anything - PTFE plating for the arm of the Space Shuttle is done in a clean-room environment.
8) Moly has a much higher film strength - PTFE does not.
9) I found a gear company that makes a big deal about applying a PTFE coating to its ring and pinion gears. This makes no sense, esp. since the EP addtives in GL-5 gear oils are designed to work on and into the metal, and the OTFE would interfere with that process, leaving only the PTFe trying to cope with high loads - it cannot.
etc, etc,
Originally Posted By: MolaKule
Do a search in this thread for "PTFE"
"And Dr. F.G. Reick, who first patented the colloidal dispersion of PTFE (Pat. 4,224,173), never did prove that his dispersion of PTFE bonded to metal and if so, how it did not shear from metal, supposing it ever did bond to it."
"It is also surmized that at localized hot spots the tetrafluoroethane decomposes such that the fluorine exudes from the particle and sticks to metal causing localized pitting.
Did I mention that it makes a descent grease thickener????"
"What does Teflon do under EP conditions???
It shears like crazy.
The only advantage to using PTFE's in gear boxes is that it reduces gear noise because of it's sound absorbing properties.
It is also a descent a Grease thickener. As a lubricant, forget it!"
Originally Posted By: Bror Jace
Yep, no ejimikated lubophile takes PTFE seriously as an internal comblustion engine lubricant anymore.
Dyno tests show reduced friction for more power and mileage but UOAs (one on this site using Tufoil) seem to indicate increased wear at the same time. The theory is that the teflon particles cause localized lubrication starvation and that's where the additional wear comes from.
--- Bror Jace
