I flush fluid annually. Never once has it come out nasty or anything but mostly clear. DOT3. Thought it might change as I started trapping at 190 plus, and it didn't. I have thought about other fluids. But.....why?

quote:

I have thought about other fluids. But.....why?

DOT 4, higher boiling point (safety margin) and completely comparable with DOT 3. Interestingly my 2012 Corvette calls for DOT 3 in the brake system but DOT 4 in the hydraulic clutch. But why? I suspension the high heat environment the clutch slave cylinder lives in demands the superior performance of 4. I would assume the brake system generally gets by with 3, and since 4 is more expensive it would have a negative effect on pricing and / or the bottom line to put 4 in every car off the line. Just an observation as to "why".

quote:

Originally posted by Bucky:
I flush fluid annually. Never once has it come out nasty or anything but mostly clear.

Only with your shyt box! meanwhile every brake system I have flushed, in a race car, my cars and others over the past 3 decades, the fluid looked and smelled like shyt after a full season of weekly racing when dot3 and dot4 were being used, never with dot5 which is the only fluid I’ll use in my cars.

I have always used DOT 3 fluid in all my race cars pretty much because I never had any issues or even really thought about. However, Ed is correct about DOT 5 not having any black stuff in the lines. I work on fleet vehicles with DOT 5 fluid and the fluid is always clear coming out of the bleeders. The master cylinder still has dark scum in it, but the fluid is clean.

My master cylinder in the dragster is clear plastic Tilton and never had dark scum in it.

Had to happen sometime. Ed and I agree on something.

Dang I was hoping with the odds that it would winning lottery instead. LMAO

quote:

Originally posted by Mike Nitzsche:
I have always used DOT 3 fluid in all my race cars pretty much because I never had any issues or even really thought about. However, Ed is correct about DOT 5 not having any black stuff in the lines. I work on fleet vehicles with DOT 5 fluid and the fluid is always clear coming out of the bleeders. The master cylinder still has dark scum in it, but the fluid is clean.

I don't know where all the contamination is coming from for some. Some people can mess up a one car funeral.

quote:

Originally posted by Canted Valve:

quote:

I have thought about other fluids. But.....why?

DOT 4, higher boiling point (safety margin) and completely comparable with DOT 3. Interestingly my 2012 Corvette calls for DOT 3 in the brake system but DOT 4 in the hydraulic clutch. But why? I suspension the high heat environment the clutch slave cylinder lives in demands the superior performance of 4. I would assume the brake system generally gets by with 3, and since 4 is more expensive it would have a negative effect on pricing and / or the bottom line to put 4 in every car off the line. Just an observation as to "why".

Seems like there is a temperature advantage if needed.

Changing out my DOT 4 brake fluid on the race car for DOT 5.1

2BKING

yes on the 5.1 been using Willwoods 570 high temp which is 5.1 for years great stuff

Where's Edward?

quote:

Originally posted by TheBlueTruck:
Where's Edward?

Who gives a shyt…

First easy guys no sense giving reason for reboot on that subject.

Second m an talk about digging post up from the graveyard.


I have run dot 5 for years in harleys for paint protection with brake cylinder above tank. I would bet car and trailer you can not be as hard on fluid as I am when riding bike. WIDE OPEN hit brakes as hard as can get by with into the corner and back full throttle until hitting binders hard again. In mountains with curves, I abuse the hell out of them.

Would not run anything else if can choose. JMO

Hellnot even had . Oops about to jinx myself for next year.LOL

quote:

Originally posted by TheBlueTruck:
Where's Edward?

Saw him on ClassRacer posting trying to get booted from there as well over an accusump.
Pretty sure he got booted from YB already.

Anyway, I'm sure I'm not the only one guilty of not flushing fluid enough.
My GM trucks get flushed plenty because of rusted brake lines!

Race car, not so much. When I do I prefer to gravity bleed with the it raised in the front.

In my 35+ years of being an auto/diesel tech, I've never seen one vehicle (have not worked on COPO's or Vettes) that used or recommended dot 5 fluid. It's either been dot 3, 4, or 5.1. I'm rebuilding my calipers on the dragster this winter and replacing the master. Racing brake fluid (Amsoil) is what's going back in.....

quote:

Originally posted by WHOMPWHOMP:

quote:

Originally posted by TheBlueTruck:
Where's Edward?

Who gives a shyt…

Truth

Waaayyyy back in the wayback, I used DOT 5 in Corvettes just to stop the internal moisture issues, bleeding is a challenge if you don't follow the rules, performance was fine on a Corvette that got thoroughly autocross and / or drag race thrashed every time it left the garage.

Since Valvoline came out with their synthetic DOT 3 & 4 fluid over 20 years ago, I have used nothing else, and have seen NO instances of performance issues, or internal corrosion.
Going on 24 years with the fluid in my race car.

Been using Dot5.1 for quite a while with great results. We used to use Dot 5 years ago for stuff that sat around and show car stuff. Only reason was moisture and it would not attack paint if it got spilled. Quit doing that a long time ago.

Like I have said in the past, I'll use what the manufacturer recommends in their brake system.

All the experts say not to mix silicon based brake fluid with glycol based. And only to use dot 5 with a new (dry) system.

But, what do I know.

quote:

Originally posted by TomR:
Like I have said in the past, I'll use what the manufacturer recommends in their brake system.

All the experts say not to mix silicon based brake fluid with glycol based. And only to use dot 5 with a new (dry) system.

But, what do I know.

"What do I know?"

Enough to follow Manufacturers recommendations.......