Can you mix Sythenthic DOT3- DOT4 Brake Fluid
04-14-2009, 10:28 AM
#1
Safety Car
Thread Starter
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
Thanks
04-14-2009, 11:56 AM
#2
Racer
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-
At the least heres a bump-
04-14-2009, 12:58 PM
#4
Safety Car
Thread Starter
04-14-2009, 01:20 PM
#5
Le Mans Master
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
http://www.valvoline.com/pages/produ...sp?product=138
Its dry/wet boiling points are 480*/311*, btw.
TSW
04-14-2009, 01:30 PM
#6
Safety Car
Member Since: Jun 2004
Location: Beecher Illinois
Posts: 4,236
Likes: 0
Received 170 Likes
on
137 Posts
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
http://www.valvoline.com/pages/produ...sp?product=138
Its dry/wet boiling points are 480*/311*, btw.
TSW
04-14-2009, 03:30 PM
#8
Melting Slicks
Member Since: Feb 2001
Location: Europe , Luxembourg
Posts: 3,303
Likes: 0
Received 3 Likes
on
3 Posts
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. Günther
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. Günther
04-14-2009, 05:03 PM
#9
Melting Slicks
Member Since: Feb 2002
Location: Cut n Shoot TX
Posts: 2,625
Likes: 0
Received 0 Likes
on
0 Posts
04-14-2009, 08:23 PM
#10
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!!
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!!
04-14-2009, 10:17 PM
#11
Team Owner
Keep your seatbelt cinched up tight....
04-15-2009, 12:34 PM
#14
Safety Car
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
Hans
