Brake Fluid...

adampv6 · Post by **adampv6** » Thu Jun 14, 2007 7:45 pm

Hi all, been a while since I was on here, 40,000 miles a year keeps you busy!!

Anywan, I've invest in a full set of black diamond discs and pads and goodridge hoses. I'm looking at buying some decent brake fluid next but I can't find my manual and I'm wondering how much I need to buy to replace the whole system?

any help would be much appreciated, cheers.

Harshan · Post by **Harshan** » Fri Jun 15, 2007 12:02 pm

I've done mine with two cans of lockheed 400ml - dot 4

Molly's Dad · Post by **Molly's Dad** » Fri Jun 15, 2007 5:19 pm

I've just done my 2-yearly brake fluid change and it took only 500ml of Comma DOT4 synthetic.

jameslxdt · Post by **jameslxdt** » Fri Jun 15, 2007 8:46 pm

ATE super blue DOT 5.1, very hard to get hold of though, Euro car parts used to stock it though im not sure now

adampv6 · Post by **adampv6** » Fri Jun 15, 2007 9:21 pm

I was looking at.......

http://www.demon-tweeks.co.uk/products/ ... de=CAS1775

Any good?

jameslxdt · Post by **jameslxdt** » Fri Jun 15, 2007 9:25 pm

thats only DOT 4, if you can find similar but in 5.1 it will have higher boiling point

adampv6 · Post by **adampv6** » Fri Jun 15, 2007 9:29 pm

Is DOT5.1 OK for our shitty peugeot systems? I was talking to a mate who mods volvos and he said no volvo system can take it without modifications

jameslxdt · Post by **jameslxdt** » Fri Jun 15, 2007 9:33 pm

well as a Volvo technician i will answer this, DOT 5.1 brake fluid is designed for extreme high temperature applications, usually where traction control is concerned, as most Volvo's have traction control it should be used, but i have never put it in any car at work, the only thing most people think will happen is it will damage the master cylinder or ABS system (which on a Volvo rarely works

) so there will be no problem with using 5.1

adampv6 · Post by **adampv6** » Fri Jun 15, 2007 9:46 pm

Well to be honest mate, I'm not planning on entering the BTCC or anything, so you may ask why the expensive brakes, the answer to that is because I wanted to and its only 50 quid more than peugeot want for their parts!

V6Exec · Post by **V6Exec** » Fri Jun 15, 2007 9:55 pm

It is all about chemistry

Some other car's user group

DOT 5 is silicone based. 5.1 is glycol based like DOT 3 & 4.

Compatibility of fluids and seals is an issue that I occasionally have to deal with at work

adampv6 · Post by **adampv6** » Sat Jun 16, 2007 12:46 am

So what are we saying here, 5.1 rather than 5 because it's similar to 4? Sounds good to me!

Malachy · Post by **Malachy** » Sat Jun 16, 2007 9:28 am

jameslxdt wrote:well as a Volvo technician i will answer this, DOT 5.1 brake fluid is designed for extreme high temperature applications, usually where traction control is concerned, as most Volvo's have traction control it should be used, but i have never put it in any car at work, the only thing most people think will happen is it will damage the master cylinder or ABS system (which on a Volvo rarely works ) so there will be no problem with using 5.1

dot 5.1 boiling point is 30c higher 260c over 230c (which i personally would not call extreme high temp) than 4 however it is far more hygroscopic this in turn lowers the boiling point as it absorbs water. to the point that is incredably likely that after 12 months of use the dot 5.1 in your car has a lower boiling point than the dot4 that is in your neighbours car and was changed the same time.

dot 5.1 is fine but it requires more regular changing of fluid 12 months or so would abe a reasonable time span. dot 4 would not need to be changed as often.

Post by **DaiRees** » Sat Jun 16, 2007 9:46 am

So is there any special process to changing the fluid on these modern cars with ABS, I've only ever done in on old "standard" brake sytems.

My fluid is 5 and a half years old now

Also is there any way to know for sure when the new stuff is coming through, or do you have to rely on the "that must be enough" method?

Malachy · Post by **Malachy** » Sat Jun 16, 2007 9:57 am

DaiRees wrote:So is there any special process to changing the fluid on these modern cars with ABS, I've only ever done in on old "standard" brake sytems.

My fluid is 5 and a half years old now

Also is there any way to know for sure when the new stuff is coming through, or do you have to rely on the "that must be enough" method?

i have abn "eezi-bleed" pneumatic bleed kit (you run it off a car tyre or compressor)i just run it with no fluid in and open a bleed nipple until no fluid comes out this shows me that there is no fluid in the line and only air, i repeat for all 4 wheels.
then i put fluid in the bleed kit and repeat the process but until fluid flows freely out of each nipple.
Job done ;). makes bleeding brakes a piece of cake and a one man job, just make sure that the fluid resevoir on the kit does not run out or you will just start pumping it full of air ;P

http://cgi.ebay.co.uk/EEZI-BLEED-BRAKE- ... dZViewItem

only cheap but an absolute godsend when bleeding awkward brakes

regards
Andy

V6Exec · Post by **V6Exec** » Sat Jun 16, 2007 12:29 pm

Malachy wrote:
jameslxdt wrote:well as a Volvo technician i will answer this, DOT 5.1 brake fluid is designed for extreme high temperature applications, usually where traction control is concerned, as most Volvo's have traction control it should be used, but i have never put it in any car at work, the only thing most people think will happen is it will damage the master cylinder or ABS system (which on a Volvo rarely works ) so there will be no problem with using 5.1
dot 5.1 boiling point is 30c higher 260c over 230c (which i personally would not call extreme high temp) than 4 however it is far more hygroscopic this in turn lowers the boiling point as it absorbs water. to the point that is incredably likely that after 12 months of use the dot 5.1 in your car has a lower boiling point than the dot4 that is in your neighbours car and was changed the same time.

dot 5.1 is fine but it requires more regular changing of fluid 12 months or so would abe a reasonable time span. dot 4 would not need to be changed as often.

Simply incorrect there old chap - there is no evidence to suggest that 5.1 is more hygroscopic than 4.