Brake Fluid

[fastblackmerc]

When I replaced my brake master cylinder, my mechanic bleed the system the old way, then hooked up his snap-on scan tool to cycle the abs pump method and then did the old way again.

If you are careful you don't need to cycle the ABS pump.

[Rockettman]

Hi "Mebot" (Ryan); I unfortuately have not got around to replacing the hoses yet.
(Last year was a very tough year for me; so not much was done with the car at all).
Sorry for the late reply.

[Mebot]

Hi "Mebot" (Ryan); I unfortuately have not got around to replacing the hoses yet.
(Last year was a very tough year for me; so not much was done with the car at all).
Sorry for the late reply.

Hi Barry thanks for the reply and no worries. I replaced the brakes and lines last summer and it was a fairly easy project. I hope things turn around for you

[Logizyme]

DOT 3 is DOT 3... there is a minimum spec that determines the DOT #.

I'd just get a name brand DOT 3 brake fluid.

The best is DOT 5.... but you'll have to flush the system with alcohol to get rid of all the DOT 3 before you go to DOT 5 and even then you may have issues with seals since the chemical composition of the different DOT# vary and using a different DOT# my cause the seals to fail.


http://en.wikipedia.org/wiki/Brake_fluid

http://www.stoptech.com/technical-su...rs/brake-fluid

Please no one attempt to switch to DOT5!

DOT3, DOT4, and DOT5.1 are Glycol based, DOT4 has higher temp and moisture tolerances than DOT3, and DOT5.1 higher than DOT4. 3/4/5.1 are hygroscopic and will function as intended in our brake system.

DOT5 is silicone based, functions differently than 3/4/5.1. DOT 5 is hydrophobic. Silicone based DOT5 is typically used in industrial and military applications, as it has a more stable viscosity in a large variety of tempuratures. The two major problems with attempting to use DOT5/silicone based brake fluid in a system designed for DOT3/4/5.1 is that the rapid vibration and agitation of the ABS(when activated) will cause silicone based brake fluids to loose their hydraulic properties, and there is no way to bleed water from the brake system, which will cause excessive corrosion and reduced hydraulic effectiveness.

Please thank the United States Department of Transportation for making Glycol/Silicone based fluids so confusing by labling Glycol 3/4/5.1 and silicone 5. Allot of sense went into that.

Brake fluid is marketed in allot of ways, Super DOT4 generally means the boiling point is much higher than DOT4 spec, there are also low viscosity brake fluids, such as Ford's DOT4LV that they use in newer applications(not recomended for our application). Generally your parts stores will not carry DOT5.1, I would suggest getting a premium DOT4, or DOT4 super, and flushing the system.

DOT3/4/5.1 can be mixed, but I would do my best to flush the entire system if switching to a new brake fluid.