brake fluid screw-up (1 Viewer)

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I am on the final stretch of my knuckle job and went to bleed the brakes. Being tired and not paying attention, I added some DOT 5 brake fluide (silicone stuff) to my DOT3 brake fluid. When I got through bleeding the brakes, the waste fluid was like oil and water, a distinct line. THat was my first clue that I had screwed up big time. I assume that I should competely empty the system and start over. Any suggestions on how to "get 'er done" the easiest? Or, have I messed up the rubber stuff...hopefully not. The DOT 3 was looking pretty funky anyway.
 
Just had to do some research on DOT 5 fluid the other day at work for a boat trailer I was replacing the disc brakes on. It called for DOT 5, and I had never used it before. As you found, the DOT 5 and the DOT 3 don't mix, and it will supposedly start to gel over time. As far as flushing it at home, the only way I know of is either bleed and bleed and bleed until it's all clean, or get a Mity vac or other hand operated brake bleeding vac system. There are a few different ones available. Most bigger shops, or tire service shops will have a brake flushing system, if you can get it to one. As far as the "rubber stuff", you should be fine. No harm done. You can run DOT 5 in most systems (not ABS systems). It is actually very good fluid. It has a much, much higher boiling point, won't absorb water, and won't damage paint. Most commonly it is used in HI-PO applications. I.E. motorcycles, race cars, etc., because of its high boiling point, which if memory serves is around 535*?
 
Brake fluid is pretty cheap - flush with a few quarts and you should be good.
 
DOT 3 and DOT 4 fluid is cheap. DOT 5 is not. Shop cost is about $140 gallon. :) Lucky you aren't actually going to use the DOT 5.
 
Is DOT 5 the silicon stuff? Its supposed to give a squishier pedal feel because it compresses unlike the standard stuff AFAIK.
 
Is DOT 5 the silicon stuff? Its supposed to give a squishier pedal feel because it compresses unlike the standard stuff AFAIK.

Yes DOT 5 is the silicone fluid. It's also blue. Kind of irrellavent, but interesting. Makes it easy to tell them apart. In rare occassions, you may find it bright yellow.
 
some more facts on dot 5 brake fluid
higher boiling point
does not absorb moisture (dot 3 does)
dot 5 does not have to be changed nearly as often as dot3 (I flush my brakefluid at 30000 miles when using dot 3)
Is compatible with most brake systems
High cost . because dot5 does not absorb moisture is a good reason to use . if you have looked at some calipers after 60000 miles using dot 3 and they have never been flushed they will show signs of interior corrosion and will lead to leaky brake components. since dot 5 does not absorb moisture but displaces it , Hydraulic brake components will last longer . I use dot 5 on all of my Ski lift Applications and I think it is worth the extra money my .02 cents
 

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