Thoughts on brake fliud

[Knucklehead]

Ok, apologies, not the most exciting post.....

Next job on the list is flushing out the brake/clutch fluid on my '93.
Read this thread:http://www.landcruiserclub.net/forums/showthread.php/41011-Brake-Fluid-explained?highlight=brake+fluid

and got me thinking that the DOT3 is the recommended fluid for my cruiser 20 years ago when there was probably little more choice available than now.

I was about to go down the fully synthetic path till read the thread talking about lack of lubricant for those of us unlucky enough to have ABS fitted.

So wondering for anybody else who has done a full flush of brakes/clutch what they used - dot 3, 4 ,5 fully synthetic or not.
Is there any advantage going up to DOT4/5 with the increase in cost?

Cheers
Dave.

 

[Knucklehead]

Wow, nobody????

The lack of reponses could only be due to one of the following:
1)Subject too boring to merit replies - possible
2)Nobody has completely flushed out their old fluid - unlikely
3)Made the mistake of introducing myself before asking the question - winner

Ok so here goes with a different approach...
Hello, I need help, I'm new to the forum, my name is david.
what brake fluid are you guys using DOT3,4,5 fully synth or not?
Don't expect any thanks for advice as this will likely be my only post and I will disappear without a trace, unless of course I need more help.

Sorry, bad day a work.

 

[frank rabbets]

Well your topic has only just arrived on my computer this second. Bloody TALKTALK are delaying my emails and now other stuff!! Or are you with TALKTALK in which case they could have delayed your post arriving here ?

I flushed mine recently and by your post might have used the wrong stuff so I'll go and check.

 

[Chris]

Option 4

Maybe you're just over thinking it. It's not F1.

I think you might have frightened us off. I just put brake fluid in mine. I buy it in 4 litre cans marked brake and clutch fluid. I've never flushed my system but I have emptied it and filled it back up lots of times.

There is clearly as much to fluid as there it to engine oil. So I am not saying you're wrong. I just pick up what's on the shelf in the local car parts store. Given it's a 20 year old 4x4 I am guessing it doesn't need distilled rainbow dew in it.

But I'll follow your lead with interest. Go for it!

 

[frank rabbets]

The book says DOT3.

I happened to have AP racing formula DOT 5.1 and put that in. I've checked the bottle and it's compatible with all the DOTS thank goodness. Had me worried for a bit.

 

[frank rabbets]

P.S Stops like a rocket now .

 

[Gary820]

I used dot 4 when did a fluid change/flush. No other reason then it's free from work and I'm a tight Yorkshire man

 

[chapel gate]

hello david and welcome.

i used dot 4 synth. thats what the auto parts fella handed me after looking in his big book. says suitable for dot 3 on the back

 

[Lorin]

I flushed my whole system and replaced fluid with dot 5.

 

[David]

I just put DOT4 in everything

 

[Mblinko]

DOT4 in mine, all fine so far. Some on iH8Mud will argue it rots seals in the long term. I'm no chemist, so can't comment.

 

[Gary Stockton]

Characteristics of common braking fluids[1]Dryboiling pointWet boiling pointViscosity limitPrimary constituentDOT 2190*°C (374*°F)140*°C (284*°F)*?Castor oil/alcoholDOT 3205*°C (401*°F)140*°C (284*°F)1500 mm2/sGlycol EtherDOT 4230*°C (446*°F)155*°C (311*°F)1800 mm2/sGlycol Ether/Borate EsterDOT 5260*°C (500*°F)180*°C (356*°F)900 mm2/sSiliconeDOT 5.1260*°C (500*°F)180*°C (356*°F)900 mm2/sGlycol Ether/Borate Ester

Wet boiling point defined as 3.7% water by volume.

 

[Gary Stockton]

Bet messy but from Wikipedia. The dot ratings refer to boiling point amongst other things

 

[Knucklehead]

Ha, I knew the new member approach would work
Thanks for thoughts.

Im with Chris on the 'option 4' and over thinking except when I read the info in the link I posted.

I get DOT4 fully synth for next to nowt at work and was going to use it.
That was until I read about it maybe causing issues with the ABS pump on the link.

Over thinking this, probably, but that is one expensive bit of kit to stuff up and is there really any benefit over the old recommended standard DOT3 stuff. Debatable.

Cheers,
Dave.

 

[wobbly]

I reckon if changing the brake fluid then the bigger issue will be the plunger on the master cylinder, not which fluid you put in.

Think its been commented on here recently, when the fluid is removed the plunger drops down and picks up crud/gunge it normally wouldnt, so when its refilled it feels like the brake isnt working at full pressure.

 

[Dave2000]

DOT 4, block of wood under the brake pedal to prevent excessive travel or vacuum....JD!

regards

Dave

 

[frank rabbets]

"DOT 4 rots seals" in a DOT 3 car I assume. I don't think so.

David are you with TalkTalk?

 

[Knucklehead]

"DOT 4 rots seals" in a DOT 3 car I assume. I don't think so.

David are you with TalkTalk?

No Frank, we made a change over to BT a couple of months ago but unless you enjoy spending endless hours to Indian call centre fixing issues, I wouldn't jump at it.

Anyhow, for me it was more the bit in 'oilman's' post about "silicone fluid is a poor lubricant and does not lubricate ABS pumps as well as PAG fluids" that got me but as there seems to be plenty who use it without issue then I'll do the same.

Cheers,
Dave.