Silicone Brake Fluid, Anyone Use It?

[Simes 248 2 Cars]

I've just changed replaced all my brake pipes and overhauled my rear calipers....only taken me 2 years to get around to.

I'm using Silicone fluid now as I've a chance to..I've filled and bled the system using a pressurised one man jobby which has done the job fine. Once I find an assistant I'll give it another go the proper way.

 

However I now read that silicone fluid gives you an even longer pedal travel (sods law I read this afterwards)

and it does.

 

Has anyone else noticed this?

[Super Josh 4]

I did wonder why you said you were going to use it It's well documented that it is quite a compressable liquid. I would have just used a decent DOT 5 or 5.1 high boiling point fluid, whichever is the decent one to use.

 

 

 

 

Josh

[hengti 2]

bought some of this a while ago (expensive!) and didn't use it due to all that's written about it

 

eg: http://www.911handbook.com/articles/pw_sil...brakefluid.html

 

i've even read advice suggestioning that seals can be compromised unless the system is flushed before changing between normal/silicon

[309PUG 2 1 Cars]

I have been advised on numerous occasions NEVER to use silicone brake fluid

[hengti 2]

i'd seek professional advice before going on; maybe someone on here can offer advice with authority?

 

hope it's not (potentially) as bad as some sources seem to suggest

[Ryan 99]

I have been advised on numerous occasions NEVER to use silicone brake fluid

Same here.

 

The handbook only recommands DOT3, so DOT4, or 5.1 would surely be good enough, even for track work?

[Chris H 10]

What you want is a super dot 4, the high temp version of std Dot4....its what we use in our WRC cars.

 

Dot 5.1 is good untill you exceded its limits then its scrwed as you end up with loads of tiny little bubbles rather than big ones you can easily bleed out.

 

As for most of the cheap silicone fluid, i've never personally used them but not ever heard a good word from people who have tried them but Castrol SRF is supposed to be the dogs danglies and is used by many proffesional teams but its aboy £30 a litre so its certainly an expesive upgrade.

[sutol 0]

Castrol SRF is supposed to be the dogs danglies and is used by many proffesional teams but its aboy £30 a litre so its certainly an expesive upgrade.

 

I use Castrol SRF and can recomend it. The pedal stays hard even when the pads are on fire!!. Also it mixes with the stuff that is already in the system so no nasty suprises if you don't flush all the old stuff out.

[TKH 0]

I tend to recommend people not to use a pressure bleed. If you have used a pressure bleed and it does not work very well try doing it the old school way and pump a full system volume of fluid through again. With the Pressure type bleed I often see air trapped in the master cylinder.

 

As for fluids avoid silicone fluids. There are many reason for this ranging from it actually damaging some systems not intended for it to its need to be bleed constantly due to it pooling moisture at the calliper.

 

Race fluids are good and have high dry and wet boiling points. But be warned most race fluids have a very short service life. Take Castrol SRF for instance as its cropped up. It is also what I use. Hands down this is a great performing fluid. But with it only able to hold its performance for a few months and that is from just opening it. If your actually using it that is greatly reduced. So not one for the road cars out there, more so when you consider the cost of the stuff.

 

For most people you will be best just to use a good quality branded performance road fluid. These are available for many people such as Castrol, AP, Motul and many others. But the most important part is at the cost of them you can afford to renew it so its always working well for you. Better to have new good fluid than well past it what was race fluid after all.

[Simes 248 2 Cars]

Oh well, by the time this debarcle is over I'll have spent the best part of £70 in fluid!!

 

I have just invested in 5L of cheap s*it Dot 4 fluid to flush the system through, and I'm going to strip down the calipers master cylinder, they've already all been off once this week.

 

Bleed it with the eezi bleed until my assistant returns and bleed through again with some decent fluid.

 

What happened to Castrol Super Response...that stuff was fantastic?

[Chris H 10]

I used to use the Castrol Super Dot4 and it was very good then i managed to get a few cases of Lucas Grand Prix brake fluid cheap and that was really good, it aparantly is the same as AP600 but i was paying about £8 a litre...but is now no longer avalible.

I'm currently using the Brembo LCF competition fluid......because a i can get it from work foc! I believe its about £14 per 500ml retail