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cheyenne10 10-27-2004 10:20 AM

brake fluids?
 
Standard brake fluid I believe is DOT 3 rated. (the kind that eats paint). Does anyone have any experience with the synthetic DOT 5 version? The Dot 5 stuff I just saw was purple colored and also listed a higher boiling point. After painting master cyl. up and the going thru install and bleeding I got some paint peeling problems with DOT 3. :banghead:

Next time I want it to look good when done. :confused:

Tx Firefighter 10-27-2004 10:27 AM

Lots of old car guys use Dot 5 synthetic becasue it's non-hydroscopic.

It lends itself well to cars that set around for long periods of time.

rickspickuppart 10-27-2004 11:05 AM

we use Dot 5 in most of the restos we do mainly because it is more resistant to eating off paint (But over time it will destroy paint unless it is cleaned off), it is alot more difficult to bleed out because it a bit thicker and also it doesn't mix w/ dot3 because it is silicone based.

Also be ready to spend some money if you go w/ dot 5 the stuff is waaaay overpriced and other than the "not eating paint" property of DOT 5 you won't notice any big advantages from it (it's designed mainly for road racing because it is more resistant to expanding/boiling under extreme heat conditions).

Dean 10-27-2004 11:13 AM

I use the silicon brake fluid in the old Vettes. It doesn't absorb the moisture like the old stuff. It will not mix as they said above. you need to bleed all the old stuff out first. And it is more expensive.

Budweis 10-27-2004 11:40 AM

i use it for same reason dean mentioned bout not absorbing moisture, i wasnt even aware it doesnt eat paint. make sure you evacuate lines well of old stuff before using. i took my lines off on last one and blew them out with air to get the old stuff out. im going to use on my truck project but replacing all the lines on it so wont have to worry bout it this time.

passthebuck 10-27-2004 11:57 AM

i considered the dot 5 stuff - i understood that the system must be 110% free of dot 3 before you install it. I also understood that it absorbes air rather than water. I went with the ford (ack, I know) dot 3 because its rated like 100deg higher than reg dot 3 & its totally compatable & if I ever need to add fluid on the road, its easily availible. Check into the FERD stuff.

neonlarry 10-27-2004 02:13 PM

I use dot 4 fluid higher boiling point than dot 3 not as hydroscopic either. As mentioned above dot 5 tends to aerate rather easily which leads to a spongy pedal feel.


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