[GYPSYGAL]

Hi all - it's me again once more! Have to have brake fluid added to my 1999 1500SE trike - can DOT 5 be used after flushing instead of DOT 4 - not sure - help!!!

 

[joe in calif]

Same Question, same answer NO!!!!!!!!!!! use DOT 4 Or DOT 3 ONLY

 

[detdrbuzzard]

i would skip the dot 3 brake fluld and stay with dot 4 for the higher boiling point

 

[tfdeputydawg]

The ? would be why???

 

[Peppyone1955]

Can DOT 5 Brake Fluid Be Used Instead of DOT 3 or 4?

DOT 5 brake fluid is silicone based. DOT 3 (standard) and DOT 4 (heavy-duty) are glycol-based. It can be distinguished from conventional brake fluids by its purple color (which comes from a dye).

Silicone does not absorb moisture. DOT 5 brake fluid does not become contaminated with moisture over time as conventional DOT 3 and 4 brake fluids do. Silicone is also chemically inert, nontoxic and won't damage paint like conventional brake fluid. It also has a higher boiling point.

Because of this, it is often marketed as a premium "lifetime" brake fluid. It is often used to preserve brake systems in antique vehicles and those that sit for long periods of time between use.

DOT 5 silicone brake fluid is also very expensive (costing four to five times as much as ordinary brake fluid), and it won't mix with glyco- based brake fluid (creating concern over sludging if all old fluid isn't removed when a system is refilled with silicone).

Silicone also has slightly different physical properties and compressibility, making it unsuitable for ABS systems calibrated to work with DOT 3 or 4 brake fluid.

 

[tfdeputydawg]

OK-had this discussion before-if the system is sealed, which it is, properly bled, etc. how is any moisture going to get in? Do worry about explaining, I've read all the experts article and I don't believe them. As long as everything is as it should be, there will be no moisture present.

 

[trike lady]

DOT 5 was design for racing applications and some HD bikes used it.
If the system calls for DOT 3 or 4 you should use it.

 

[budoka]

In a perfect world, the sealed environment prohibits moisture from accumulating. However, as there is a small amount of airspace in the reservoir(s), condensation can occur under extreme conditions. I'd stick with the type embossed on the lid.

 

[tfdeputydawg]

In a perfect world, the sealed environment prohibits moisture from accumulating. However, as there is a small amount of airspace in the reservoir(s), condensation can occur under extreme conditions. I'd stick with the type embossed on the lid.

So, what function do the "bellows" that are in the reservoirs perform, once the system has been properly bled and ALL air has been removed

 

[GYPSYGAL]

Thanks again!

Thank you for your input - DOT4 it is and will always be. The reason I asked was because someone who rides HD suggested it and I didn't know the difference!