$projecthp
  • Do NOT use the new DOT 5 Brake fluid!
  • Do NOT use the new DOT 5 Brake fluid!
  • Do NOT use the new DOT 5 Brake fluid!
  • Do NOT use the new DOT 5 Brake fluid!

Results 1 to 10 of 10
  1. #1
    Member stevolwevol's Avatar
    Join Date
    May 2015
    Location
    Michigan
    Posts
    173
    Corvette(s)
    1977 light blue
    Post Thanks / Like
    Rides
    0

    Default Do NOT use the new DOT 5 Brake fluid!

    I was having a discussion with the manager at a brake company, and he said the EPA forced DOT 5 brake fluid to be reformulated. He said with in a week, the o rings will be swelled up, and ruined. I was told to use DOT 3 If I change out the fluid.

    This is bad news to me, but it would be worse If I used the new junk not knowing it would damage my brakes. I just thought of passing this on to whom it may concern.
    Likes GRANDSPORT liked this post

  2. #2
    Technical Writer for Internet & Print Media
    Join Date
    Jan 2001
    Location
    CenCoast CA
    Posts
    11,936
    Corvette(s)
    71 04 12 19
    Post Thanks / Like
    Rides
    0

    Default

    What "new DOT 5 Brake fluid" are you talking about? Can you post a brand name we need to watch for? Also, can you be more specific about your source? What brake company are you talking about. Lastly, I've done a brief web search and can't find anything about the EPA forcing DOT 5 fluids to be reformulated. Typically, EPA doesn't regulate brake fluid the Department of Transportation (DOT) does that.

    "DOT 5" brake fluid is not new. It's been around for decades. DOT 5 brake fluids are all silicon-based and a popular for use in show and collector cars becuase they are not hygroscopic.

    They are not very good for high-performance use because silicone-based brake fluids can compress slightly once they get hot. Also DOT 5 fluids must not be used in any brake system which has ABS because their higher viscosities degrade ABS performance.

  3. #3
    Member stevolwevol's Avatar
    Join Date
    May 2015
    Location
    Michigan
    Posts
    173
    Corvette(s)
    1977 light blue
    Post Thanks / Like
    Rides
    0

    Default

    private message sent

  4. #4
    Member
    Join Date
    Mar 2014
    Location
    Columbus, NC/NE Georgia
    Posts
    2,293
    Corvette(s)
    1997 boosted silver coupe
    Post Thanks / Like
    Rides
    0

    Default

    DOT 5 is silicone based and DOT 5.1 is back to glycol based the same as DOT 3 and 4. Actually they are poly-glycol based..

    Here's an interesting site on the subject; in addition, it shows a compatibility chart also. Simply said, DOT 5 is compatible with no other brake fluid.
    What is the Difference between DOT 4 and DOT 5.1 Brake Fluid? | Epic Bleed Solutions



    Whoosh, and blur

  5. #5
    Administrator Tom Bryant's Avatar
    Join Date
    Nov 2000
    Location
    Edgerton, Ohio, United States
    Posts
    7,005
    Corvette(s)
    1959 black 270hp (9/2/69) 1981 Beige L81(10/20/80)
    Post Thanks / Like
    Rides
    2

    Default

    It appears the DOT 5.1 came about from a need to have a higher boiling point fluid without having to switch to silicone.

    Tom
    NCRS 1360.............SACC 2082.............C1 Registry..............L81 Registry
    1959 Chevrolet Corvette 1981 Chevrolet Corvette , 350 L81 automatic Frost Beige

  6. #6
    Member stevolwevol's Avatar
    Join Date
    May 2015
    Location
    Michigan
    Posts
    173
    Corvette(s)
    1977 light blue
    Post Thanks / Like
    Rides
    0

    Default

    Since I posted my original post I called the man I spoke with about the subject. I asked him to repeat what he told me. He also said it's ok to post the company name, and his name, so I will say it was: Muskegon Brake and Tire, Muskegon , Michigan, and the Man I spoke to is Jeff.

    Jeff told me the O rings will swell, and ruin the system with the "new" DOT 5 fluid. Not DOT 3, not DOT 5.1, it was DOT 5

    He said they were done using it, and no longer selling it. Paraphrasing, I was told "unless you have military grade O rings, they will swell".

    So to whom this may concern, I would love to be proven wrong. I do not want to have to go to a glycol based fluid either.
    Likes GRANDSPORT liked this post

  7. #7
    Member
    Join Date
    Mar 2014
    Location
    Columbus, NC/NE Georgia
    Posts
    2,293
    Corvette(s)
    1997 boosted silver coupe
    Post Thanks / Like
    Rides
    0

    Default

    Swell is 100% correct and IMO, putting it mildly..
    An O-Ring fits in an annulus (groove) and in a bore.. It stretches slightly in the groove and is compressed slightly in the bore which provides a seal.. Now, consider what happens when an O-Ring swells in the bore and groove....
    Whoosh, and blur

  8. #8
    Member stevolwevol's Avatar
    Join Date
    May 2015
    Location
    Michigan
    Posts
    173
    Corvette(s)
    1977 light blue
    Post Thanks / Like
    Rides
    0

    Default

    Quote Originally Posted by kpic View Post
    Swell is 100% correct and IMO, putting it mildly..
    An O-Ring fits in an annulus (groove) and in a bore.. It stretches slightly in the groove and is compressed slightly in the bore which provides a seal.. Now, consider what happens when an O-Ring swells in the bore and groove....
    I should have said "swells too much". I'm just going with what I was told.

  9. #9
    Member
    Join Date
    Mar 2014
    Location
    Columbus, NC/NE Georgia
    Posts
    2,293
    Corvette(s)
    1997 boosted silver coupe
    Post Thanks / Like
    Rides
    0

    Default

    Quote Originally Posted by stevolwevol View Post
    I should have said "swells too much". I'm just going with what I was told.
    You said it quite well as did your source.. I'm a retired power train design type which means I can be detail oriented to the point of being anal.

    As the clearance between the shaft and bore is only a few thousandths; I can't offer an opinion on where the swollen material will go except to say, it won't be pretty..

    Whoosh, and blur

  10. #10
    Member stevolwevol's Avatar
    Join Date
    May 2015
    Location
    Michigan
    Posts
    173
    Corvette(s)
    1977 light blue
    Post Thanks / Like
    Rides
    0

    Default

    Quote Originally Posted by kpic View Post
    You said it quite well as did your source.. I'm a retired power train design type which means I can be detail oriented to the point of being anal.

    As the clearance between the shaft and bore is only a few thousandths; I can't offer an opinion on where the swollen material will go except to say, it won't be pretty..

    As far as I'm concerned, being "anal" is the only way to fly.

Similar Threads

  1. Question: Brake Fluid
    By Vette79 in forum C3 General Discussion
    Replies: 10
    Last Post: 09-22-09, 01:03 PM
  2. ATE Brake Fluid
    By dbaumis in forum C4 Technical and Performance
    Replies: 1
    Last Post: 02-08-06, 12:12 AM
  3. ? DOT 5.1 Brake Fluid (yes, 5.1)
    By Jack in forum General Automotive Discussion
    Replies: 1
    Last Post: 06-10-05, 01:48 PM
  4. ZF6: Is brake fluid ok?
    By sothpaw in forum C4 Technical and Performance
    Replies: 14
    Last Post: 09-02-04, 08:23 AM
  5. Brake Fluid ?
    By 72 Bluz in forum C3 Technical and Performance
    Replies: 7
    Last Post: 08-25-01, 06:15 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •