Register now to get rid of these ads!

Hot Rods brake fluid

Discussion in 'The Hokey Ass Message Board' started by cycledelicjohn, Jul 15, 2016.

  1. cycledelicjohn
    Joined: Mar 9, 2008
    Posts: 687

    cycledelicjohn
    Member

    IS THERE ANY SIMPLE WAY 2 TELL IF U HAVE DOT 3 OR 4 - OR SIMPLY 5 IN YOUR EXISTING BRAKE SYSTEM WITHOUT A CHEMICAL ANALYSIS ???
     
    270dodge likes this.
  2. Unscientific way is DOT 3 and DOT 4 will ruin paint.........
     
  3. chopolds
    Joined: Oct 22, 2001
    Posts: 5,680

    chopolds
    Member
    from howell, nj
    1. Kustom Painters

    The silicone DOT 5 I have used is colored purple.
     
  4. jkeesey
    Joined: Oct 12, 2011
    Posts: 652

    jkeesey
    Member

    Take a small amount of what you have in the master and mix it in a glass with dot 5 in it. If it looks like salad dressing and doesnt mix you have dot 3.
     
    Register now to get rid of these ads!

  5. 19Fordy
    Joined: May 17, 2003
    Posts: 6,592

    19Fordy
    Member

    DOT 3 and 4 are compatible. Just don't mix any DOT 5 in it.
    You probably already know this.
     
  6. Gene Boul
    Joined: Feb 9, 2006
    Posts: 807

    Gene Boul

    Count the dots!
    Seriously, take a syringe and suck out whats in the MC reservoir and add what you want. You might add "the new stuff" and repeat as above then go forward with the new juice...just saying!
     
  7. DO NOT do this! If it has DOT 5 and you add 3 or 4 (or vice versa) the remaining fluid in the limes and calipers/wheel cylinders will not mix and they will at minimum become gummy and loss of brakes is eminent. Really bad idea.
     
  8. vickckik
    Joined: Dec 21, 2011
    Posts: 70

    vickckik
    Member

    Take the car to a service center like Jiffy Lube and have the brake system flushed and filled with the type fluid you choose. They will generally charge about $100.
     
  9. yellow dog
    Joined: Oct 15, 2011
    Posts: 407

    yellow dog
    Member
    from san diego

    DOT 3,4 and 5 have progressively higher BP's. Look them up if you want to check using the BP
    method.
    Since DOT 3 and 4 are compatible, no problem. They are also good absorbents for water. DOT 5
    is not miscible with water which is its disadvantage. Sample some of you MC fluid and add
    a small amount of water in a transparent container....watch the interface layer. If it the layers stay separate, its DOT 5
     
  10. jcmarz
    Joined: Jan 10, 2010
    Posts: 4,636

    jcmarz
    Member
    from Chino, Ca

    I usually go with these dots
    dots.jpg
     
  11. Morrisman
    Joined: Dec 9, 2003
    Posts: 1,600

    Morrisman
    Member
    from England

    3, 4 and 5.1 are the same type, but 5 is some synthetic silicon stuff that doesn't damage paint, but DOES eat rubber.

    God only know why they numbered 5.1 like that. I bought some for my Sportster, after the store dork told me "It is virtually the same as 5". No, dork, it is totally different.
     
  12. yellow dog
    Joined: Oct 15, 2011
    Posts: 407

    yellow dog
    Member
    from san diego

    DOT 5.1 has a 10*C higher BP than DOT 5.....apparently numbered solely based on BP
     
  13. Morrisman
    Joined: Dec 9, 2003
    Posts: 1,600

    Morrisman
    Member
    from England

    So why not DOT 3, then DOT 3.1?
     
  14. manyolcars
    Joined: Mar 30, 2001
    Posts: 8,152

    manyolcars

    Do you have any PROOF that this is true?

    I have proof that this is NOT true. I poured some 3 and some 5 into a container and have been watching it since Christmas. No gummy yet!
     
  15. manyolcars
    Joined: Mar 30, 2001
    Posts: 8,152

    manyolcars

    This is DOT 5s advantage! Not disadvantage
     
  16. 325w
    Joined: Feb 18, 2008
    Posts: 5,231

    325w
    ALLIANCE MEMBER
    from texas

    Miscible ? At 71 yrs old that's a first for me.
     
  17. manyolcars
    Joined: Mar 30, 2001
    Posts: 8,152

    manyolcars

    think of it as mixable but misspelled :)
     
  18. kma4444
    Joined: Sep 24, 2008
    Posts: 197

    kma4444
    Member

    I use 5 in all my project cars, have for years. Have always put it in from an empty system. Works well, doesn't affect paint, which is why I use it. Never had any rubber failures with it.
     
  19. yellow dog
    Joined: Oct 15, 2011
    Posts: 407

    yellow dog
    Member
    from san diego

    DOT 3, 4 and 5.1 are specifically intended to absorb water. Since the MC breaths atmospheric air
    laden w/ varying amounts of water, unabsorbed water is now susceptible to freezing in cold
    winter months.
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2020 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.