seabee
Well-Known Member
Hi Gang. Going to be replacing the brake lines and flush/bleed the system and was wondering what are your thoughts on which Brake fluid and any pro tips? As always, thank you in advance.
I suggest not using silicone-based (DOT 5) fluid. Its non-hygroscopic nature (i.e., its not absorbing water) is not definitely a good thing. Moisture gets into the brake hydraulic system -- it will happen with normal usage and/or changes in ambient temperature and humidity. Ordinary brake fluid is designed to absorb and assimilate a fair amount of moisture without causing substantial corrosion problems. With silicone fluid, the water will accumulate in slugs at the lowest points of the system...and stay there, where it will aggressively corrode whatever it's touching. This is not an improvement.
Furthermore, it is difficult to get all the air out of silicone brake fluid, so it is difficult to get a good, firm pedal.
Sorry if I am hijacking this thread and I do not mean to but I have a question regarding brake fluid. Is there any difference in brake fluids in regards to heat generated by the braking system? My car does not have any brake fluid leaking but I notice if I take the car on a long trip that when I get back I notice that sometimes it almost seems as though the brake fluid is evaporating or maybe burning off? because my Master Cylinder is down a little on the front fluid side. The lines and Master and rotors and pads drums and rear wheel cylinders are all recently replaced and like I said there appears to be no leaking when the car is parked. Is there any brake fluid that stands up better under high temperatures? Dot 3, 4, 5, 5.1??????
I just had a brake class at the local college and the instructors and book suggested not using DOT 5 for the reasons that /6dan stated above. They even stated that the MFG's are going away from it.
I personally have no experience with it; I justed wanted to let you know what is being taught at the college level.