DOT 5.1 or DOT 4 Brake Fluid
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 2,608
Likes: 3
From: TEXAS - you mean there are other states?
DOT 5.1 or DOT 4 Brake Fluid
I searched the forum for info on DOT 5.1 vs. DOT 4 and found the latest thread to be from 2008.
Can ya'll offer recent input on this for my 69 streetrod with regular brakes?
I see DOT 5.1 advantage to not eat paint. Disadvantage to be that it enables water to 'pool'... ?? Is it expensive - if not just change yearly... which we should do anyway.
As for DOT 4 - its great - but eats paint... I know - what am I doing rubbing it on my paint,..... don't ask - it's Murphy's Law.
I see DOT 5 has been around for like 10 years..... where have I been - oh yeah - raising kids.
Can ya'll offer recent input on this for my 69 streetrod with regular brakes?
I see DOT 5.1 advantage to not eat paint. Disadvantage to be that it enables water to 'pool'... ?? Is it expensive - if not just change yearly... which we should do anyway.
As for DOT 4 - its great - but eats paint... I know - what am I doing rubbing it on my paint,..... don't ask - it's Murphy's Law.
I see DOT 5 has been around for like 10 years..... where have I been - oh yeah - raising kids.
Burning Brakes
Joined: Oct 2001
Posts: 911
Likes: 5
From: TN
silicone fluid
I have been using DOT5 in my 68 and 70 Corvettes for 22-23 years. The 68 has manual brakes and the 70 power brakes. I switched because I did not want to change out the DOT3/DOT4 fluid, which is hydroscopic, absorbs water.
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 2,608
Likes: 3
From: TEXAS - you mean there are other states?
Drifting
Joined: Apr 2008
Posts: 1,305
Likes: 2
From: Lewisburg WV
thegazman
If you research brakes fluids you will find that there is a difference between DOT 5 and DOT 5.1. DOT 5.1 will mix with DOT 4 as they have the same base, but DOT 5 will not as it is silicone based.
Pro
Joined: May 2003
Posts: 593
Likes: 0
From: London England
Dot 5.1 has a polyglycol base which is compatible with 3 & 4.
Dot 5 is incompatible and needs a complete system flush or should only be fitted to a clean virgin system.
IMO the boiling point advantage of DOT 5.1 over DOT 4 isn't worth the price difference unless you can get a really good deal.
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 2,608
Likes: 3
From: TEXAS - you mean there are other states?
Yeah - I am aware of those basic differences... I am not interested in 5.0 at all. Its either DOT4 or 5.1. But the advantage of not damaging paint is attractive to me. I will investigate the costs now.
Now I have new calipers, lines, etc and Master Cylinder.... But if the master Cylinder has remnants of what DOT3/4 in it from its manufacture test, do I worry about that?
Another item of importance is whether the 5.1 (since it does not absorb water) will allow pudldling of water and is that even an issue if you replace it every 12 months?
Now I have new calipers, lines, etc and Master Cylinder.... But if the master Cylinder has remnants of what DOT3/4 in it from its manufacture test, do I worry about that?
Another item of importance is whether the 5.1 (since it does not absorb water) will allow pudldling of water and is that even an issue if you replace it every 12 months?
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
Yeah - I am aware of those basic differences... I am not interested in 5.0 at all. Its either DOT4 or 5.1. But the advantage of not damaging paint is attractive to me. I will investigate the costs now.
Now I have new calipers, lines, etc and Master Cylinder.... But if the master Cylinder has remnants of what DOT3/4 in it from its manufacture test, do I worry about that?
Now I have new calipers, lines, etc and Master Cylinder.... But if the master Cylinder has remnants of what DOT3/4 in it from its manufacture test, do I worry about that?
Another item of importance is whether the 5.1 (since it does not absorb water) will allow pudldling of water and is that even an issue if you replace it every 12 months?
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 2,608
Likes: 3
From: TEXAS - you mean there are other states?
Thanks….
It appears the cost of 5.1 is about $9-$13 per Qt. Although I cannot find it locally… yet….
Is there a brand that is better? Is the 5.1 colored as well or is that for 5.0 only?
Also regarding flushing – I say I have all new parts, but technically, my valves/block fittings are old and have not been flushed – so do I still have to worry about flushing those even though they have been ‘dry’ for 7 years? Is the proper way to flush a system to assemble completely and add denatured alcohol and bleed out???? Then disassembly, bench bleed and …. Or?????
It appears the cost of 5.1 is about $9-$13 per Qt. Although I cannot find it locally… yet….
Is there a brand that is better? Is the 5.1 colored as well or is that for 5.0 only?
Also regarding flushing – I say I have all new parts, but technically, my valves/block fittings are old and have not been flushed – so do I still have to worry about flushing those even though they have been ‘dry’ for 7 years? Is the proper way to flush a system to assemble completely and add denatured alcohol and bleed out???? Then disassembly, bench bleed and …. Or?????
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Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 2,608
Likes: 3
From: TEXAS - you mean there are other states?
Gee - of course - I realized this before lunch and wanted to post that - but appreciate you clarifying that. That takes away a large hesitation I had with going with 5.1.
It seems there is no reason not to go with 5.1
I will get a few temp ratings and get back just fyi
It seems there is no reason not to go with 5.1
I will get a few temp ratings and get back just fyi
Team Owner
Joined: Sep 2006
Posts: 31,301
Likes: 4,389
From: Westminster Maryland
Hi KB,
I found the fact that the 5 or 5.1 doesn't affect paint to be a bigger plus than I thought it would be when I had a problem sealing 2 of the connections. I would have had a lot more work to do if I had a paint problem too. I think it's worth what ever effort it takes to use 5 or 5.1.
Regards,
Alan
I found the fact that the 5 or 5.1 doesn't affect paint to be a bigger plus than I thought it would be when I had a problem sealing 2 of the connections. I would have had a lot more work to do if I had a paint problem too. I think it's worth what ever effort it takes to use 5 or 5.1.
Regards,
Alan
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 2,608
Likes: 3
From: TEXAS - you mean there are other states?
Thanks Alan - yeah - I am thinking more and more of this.... but where to buy? and what brand? I tried 12 places today...
and I heard Ford went to 5.1 - so I also called Ford... but the parts dept said all they had was DOT 3
and I heard Ford went to 5.1 - so I also called Ford... but the parts dept said all they had was DOT 3
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
http://www.ferobrake.co.za/productdetail.php?id=19
Pro
Joined: May 2003
Posts: 593
Likes: 0
From: London England
Not sure where you got that info but DOT 5.1 will eat paint no differently than DOT 3 or 4.
http://www.ferobrake.co.za/productdetail.php?id=19
http://www.ferobrake.co.za/productdetail.php?id=19
To clarify one more time....
DOT 3 205°C (401°F) 140°C (284°F)
DOT 4 230°C (446°F) 155°C (311°F)
DOT 5.1 270°C (518°F) 191°C (375°F)
All polyglycol based, will all eat your paint and are hygroscopic, the main differences between them is the boiling point.
DOT 5 260°C (500°F) 180°C (356°F)
Silicone based, doesn't absorb water, doesn't damage paint, wont mix with older brake fluids and some rubber components.
Terrorizing Orange Cones
Joined: Oct 2007
Posts: 2,572
Likes: 17
From: Northern CO
Thanks for starting this thread, KB.
I'll be ready very soon to fill a currently dry system comprised of almost all new pieces. I checked my local NAPA auto parts store and they sell their branded version in the popular DOT ratings, including DOT 5.
They sell in qty's of 12oz, 32oz and 1 gal. (over $100 US for the gallon. Ouch.) As previously stated, I like the idea of it being silicone-based and promoted not to destroy paint. That sounds plenty good for my street application.
I left my disc-based AIM (Thanks for great info, Willcox!) loaded in one of the DVD trays on my home machine so do not have the capacity's chart here at the job site.
What is the total quantity required to fill a dry system on our C3's? I have all new lines, distr blocks, and calipers (VB&P) and a rebuilt MC. I'd want a little extra for bleeding too.
Thanks and a tip o'the hat in advance to whomever may provide the number.
I'll be ready very soon to fill a currently dry system comprised of almost all new pieces. I checked my local NAPA auto parts store and they sell their branded version in the popular DOT ratings, including DOT 5.
They sell in qty's of 12oz, 32oz and 1 gal. (over $100 US for the gallon. Ouch.) As previously stated, I like the idea of it being silicone-based and promoted not to destroy paint. That sounds plenty good for my street application.
I left my disc-based AIM (Thanks for great info, Willcox!) loaded in one of the DVD trays on my home machine so do not have the capacity's chart here at the job site.
What is the total quantity required to fill a dry system on our C3's? I have all new lines, distr blocks, and calipers (VB&P) and a rebuilt MC. I'd want a little extra for bleeding too.
Thanks and a tip o'the hat in advance to whomever may provide the number.
Burning Brakes
Joined: Oct 2002
Posts: 914
Likes: 14
From: Aberdeen, Scotland
Brake fluid
I must love punishment as I "like" working on brakes. I have performed several brake overhauls on my Vette, other vettes and my "normal" daily drivers.
I generally like to use ATE "SUPER BLUE .. you can find it on Motive web site. However I also just use any good DOT 4 that is availible often. This is because when I first bought the vette it had DOT 5 ... I worked and attempted to bleed the brakes to little avail. I ended up doing the switch back to DOT 4 and never looked back! For me I will never have DOT 5 in another car, the performance is not as good anthe headache not worth it.
carbster
I generally like to use ATE "SUPER BLUE .. you can find it on Motive web site. However I also just use any good DOT 4 that is availible often. This is because when I first bought the vette it had DOT 5 ... I worked and attempted to bleed the brakes to little avail. I ended up doing the switch back to DOT 4 and never looked back! For me I will never have DOT 5 in another car, the performance is not as good anthe headache not worth it.
carbster
Thread Starter
Melting Slicks
Joined: Feb 2001
Posts: 2,608
Likes: 3
From: TEXAS - you mean there are other states?
OK - the decision has been made....
I went with DOT 4. Here's the background/learning/story.....
I posted on C5 Forum on where to buy 5.1. CF Thread - Where to buy DOT 5.1
Although I finally found it at O'Reilley's (it was a Wagner FC 3300100). BUT I found that 5.1 indeed still eats paint. I confirmed this verbally with StopTech.com's tech dept. That was the deciding factor for me - so DOT 4 it is.... Happy that I did my research - happy with DOT4 and that conversion to Power Brakes is now almost complete.
StopTech.com also has an article I need to read on rotor warping (the myths)....but that's another story - check it out.
I went with DOT 4. Here's the background/learning/story.....
I posted on C5 Forum on where to buy 5.1. CF Thread - Where to buy DOT 5.1
Although I finally found it at O'Reilley's (it was a Wagner FC 3300100). BUT I found that 5.1 indeed still eats paint. I confirmed this verbally with StopTech.com's tech dept. That was the deciding factor for me - so DOT 4 it is.... Happy that I did my research - happy with DOT4 and that conversion to Power Brakes is now almost complete.
StopTech.com also has an article I need to read on rotor warping (the myths)....but that's another story - check it out.