Go Back   Corvette Forum > C3 Corvettes, 1968 - 1982 > C3 Tech/Performance
Sign in using an external account
Register Forgot Password?
Register Search Today's Posts Mark Forums Read FAQ Vendor Directory
Search
C3 Tech/Performance
V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette Sponsored by
VBP

Welcome to Corvetteforum.com!
Welcome to Corvetteforum.com.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join Corvetteforum.com today!


Corvette Store
 
 
C7 Parts & Accessories
C6 Parts & Accessories
C5 Parts & Accessories
C4 Parts & Accessories
C3 Parts & Accessories
C2 Parts & Accessories
C1 Parts & Accessories
Wheels & Tires
Sponsored Ads
 
 
Vendor Directory
  
Reply
 
 
 
 
Thread Tools Search this Thread
Old 04-14-2009, 10:28 AM   #1
spedaleden
CF Senior Member
 
spedaleden's Avatar
 
Member Since: Nov 2004
Location: Mundelein Illinois
Default Can you mix Sythenthic DOT3- DOT4 Brake Fluid

I am flushing the brake system. This is a C4 and Master says use DOT3 the fluid I have is Valvoline Synthetic DOT3 DOT4. Can I pour it in with DOT 3 or should I use plain DOT3

Thanks
spedaleden is offline   Reply With Quote
Old 04-14-2009, 11:56 AM   #2
2armor
CF Senior Member
 
2armor's Avatar
 
Member Since: Jan 2007
Location: Concord CA
Default

I believe they are compatible. The DOT 4 container says 3 / 4 right? The only difference I know of is the DOT 4 has a higher wet and dry boiling point. I've seen resorvoir lids that say dot 3 0r 4 too.

At the least heres a bump-
2armor is offline   Reply With Quote
Old 04-14-2009, 11:59 AM   #3
Wrencher
CF Senior Member
 
Wrencher's Avatar
 
Member Since: Oct 1999
Default

You can not mix synthetic with conventional brake fluid, no matter what the rating. Don't do it.

Hans
Wrencher is offline   Reply With Quote
Old 04-14-2009, 12:58 PM   #4
spedaleden
CF Senior Member
 
spedaleden's Avatar
 
Member Since: Nov 2004
Location: Mundelein Illinois
Default

Quote:
Originally Posted by Wrencher View Post
You can not mix synthetic with conventional brake fluid, no matter what the rating. Don't do it.

Hans
Thanks
spedaleden is offline   Reply With Quote
Old 04-14-2009, 01:20 PM   #5
TheSkunkWorks
CF Senior Member
 
TheSkunkWorks's Avatar
 
Member Since: Apr 2007
Location: Graceland in a Not Correctly Restored Stingray
Default

SILICONE brake fluid cannot be mixed with conventional fluids, but Valvoline Synthetic Dot 3/Dot 4 "Mixes well with conventional fluids".

http://www.valvoline.com/pages/produ...sp?product=138

Its dry/wet boiling points are 480*/311*, btw.


TSW
TheSkunkWorks is offline   Reply With Quote
Old 04-14-2009, 01:30 PM   #6
KapsSA
CF Senior Member
 
KapsSA's Avatar
 
Member Since: Jun 2004
Location: Beecher Illinois
Default

Quote:
Originally Posted by TheSkunkWorks View Post
SILICONE brake fluid cannot be mixed with conventional fluids, but Valvoline Synthetic Dot 3/Dot 4 "Mixes well with conventional fluids".

http://www.valvoline.com/pages/produ...sp?product=138

Its dry/wet boiling points are 480*/311*, btw.


TSW
KapsSA is online now   Reply With Quote
Old 04-14-2009, 01:49 PM   #7
2armor
CF Senior Member
 
2armor's Avatar
 
Member Since: Jan 2007
Location: Concord CA
Default

Silicone is DOT 5. His is syn 3/4. This should be compatible.
2armor is offline   Reply With Quote
Old 04-14-2009, 03:30 PM   #8
WESCH
CF Senior Member
 
WESCH's Avatar
 
Member Since: Feb 2001
Location: Europe , Luxembourg
Default

Hi

You can not mix synthetic with conventional brake fluid

Aren't all brake fluids synthetic except for the silicone fluid ?
I don?t know of any mineral brake fluid.

Dot 3 is well mixable with Dot 4 as mentioned B4.

Some believe that C3 systems should not be filled with Dot 4 due to premature brake piston seal failures. Something to do with a different additive or so.

Rgds. GŁnther
WESCH is offline   Reply With Quote
Old 04-14-2009, 05:03 PM   #9
VettePower
CF Senior Member
 
VettePower's Avatar
 
Member Since: Feb 2002
Location: Cut n Shoot TX
Default

Quote:
Originally Posted by Wrencher View Post
You can not mix synthetic with conventional brake fluid, no matter what the rating. Don't do it.

Hans
Geez...You need to get your facts straight before making such a grand statement.

The synthetic DOT4 is not silicone, and it can be mixed with DOT3....
VettePower is offline   Reply With Quote
Old 04-14-2009, 08:23 PM   #10
red88L98convert
CF Senior Member
 
red88L98convert's Avatar
 
Member Since: Dec 2004
Location: clovis ca
Default

good grief....I noticed that none of the naysayers said why you can't mix synthetic and standard, they just say you CAN NOT DO IT.
whatever. mix away. won't hurt anything, won't kill seals. that's a bunch of nonsense.

and by the way. I HAVE mixed regular with synthetic and haven't crashed yet!!
red88L98convert is offline   Reply With Quote
Old 04-14-2009, 10:17 PM   #11
7T1vette
CF Senior Member
 
7T1vette's Avatar
 
Member Since: Jan 2006
Location: Crossville TN
Default

Keep your seatbelt cinched up tight....
7T1vette is offline   Reply With Quote
Old 04-14-2009, 11:33 PM   #12
spedaleden
CF Senior Member
 
spedaleden's Avatar
 
Member Since: Nov 2004
Location: Mundelein Illinois
Default

Thanks Guys, I used DOT3 just to be safe
spedaleden is offline   Reply With Quote
Old 04-15-2009, 12:02 AM   #13
RobRace10
CF Senior Member
 
RobRace10's Avatar
 
Member Since: May 2005
Location: Hales Corners Wisconsin
Default

An interesting article on brake fluids:

http://www.afcoracing.com/tech_pages/fluid.shtml
RobRace10 is offline   Reply With Quote
Old 04-15-2009, 12:34 PM   #14
Wrencher
CF Senior Member
 
Wrencher's Avatar
 
Member Since: Oct 1999
Default

I should have posted in more detail. Yes, silicone is a definite no-no as far as mixing goes and yes you "can" mix the rest, but I highly recommend against it. True, you may never see a problem in a street car, but why take a chance? I flush mine annually to prevent/reduce moisture content, plus I always change it after a day of racing, and I exclusively use Ford DOT 4 fluid. Why? After 35 years of repairing and racing (IMSA, SCCA Can-Am and Trans-Am, club GT-1,2,3,4) I find what works and causes the least problems. I don't mix oil, coolant or gear lube either and it might be overkill, but I don't have problems and I've repaired other's stuff because of it. No offense to the others, but that's how I do it. The great thing about this forum, you get lots of informed opinions and you get to make a more informed decision base on that.

Hans
Wrencher is offline   Reply With Quote
Old 04-15-2009, 12:34 PM
 
Go Back   Corvette Forum > C3 Corvettes, 1968 - 1982 > C3 Tech/Performance
Reload this Page Can you mix Sythenthic DOT3- DOT4 Brake Fluid
 
 
 
Reply

Tags
84, brake, conventional, dot, dot3, dot4, fluid, ford, mix, mixed, mixing, regular, silicone, synthetic, vette


Thread Tools Search this Thread
Search this Thread:

Click for Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump


All times are GMT -4. The time now is 06:28 PM.


Emails & Password Backup

Search Engine Friendly URLs by vBSEO 3.5.2