Join Date: Apr 2002
Location: Dandridge (Near Knoxville), TN, USA
Re: Anyone switch to "Dot 5" brake fluid?
As others have said, DON'T TRY IT! To do so you would have to COMPLETELY clean the entire system out so not trace of the DOT 4 remains, a daunting task to say the least. Then you would have to worry about seal compatibility. As well as I remember though, the rubber parts were not an issue with DOT 5. Silicone is less reactive than the Glycol based DOT 4.
The silicone fluids were developed for heat resistance mostly, and used in high performance brake systems. It is not a panacea, and really does nothing for the normal street driver. In fact, it has a rather serious drawback for most street systems. Moisture will not be absorbed into it, and will eventually puddle at the lowest points in the system, where it will cause corrosion. DOT 3/4 will absorb small amounts of moisture and not let it pool in small spots.
The new DOT 5.1 is compatible though, just a shame that they did not call it DOT 6 to prevent people from ruining brake systems in the future by putting DOT 5 in systems that have DOT 5.1 in them! As DOT 5.1 becomes more used, that danger will increase.
I don't want to achieve immortality through my work...I want to achieve it through not dying.
EX: '01 Black LT, BAT BYKE (Totaled at 110,000 miles)
IBA SS, BB, BBG, 10/10ths.
No bike now, but maybe in the future.