328 silicone brake fluid changeover

best is to ask the mechanic - if you trust him to do the work he should be able to answer you, curious as to why you changed - I remember a discussion on this and I thought the concensus was it was not worth it

 

Yes. I'm also curious as to why you changed.

 

silcone brake fluid and conventional brake fluid are not compatable. If you want to do this then you will have to replace the master cylinder, all brake hoses, rebuild or replace the calipers, etc. You will also have to flush out all the brake lines in the car, And even then there is still no garentee that you have removed all the old fluid. Not really worth it IMHO.

If you track the car alot(as in almost everyweekend) and push the car's braking system to it's limits then yes it would be a worth while thing to change. But if it's just a street car with the odd track event, then just do yearly flushes of the system and you'll be just fine.

 

They are compatible, but the system will only be as good as the lesser fluid.

If you really want all the silicone fluid and nothing else, then you will need to flush it through at least twice, and use about 1.5 litres in the process.

You will NOT need to replace ANY components. Mineral oil as used in some things like Citroens' etc is not compatible, but that's all.

But, as already said, silicone fluid gives nothing to performance. It's only benefit is being paint friendly, and we can all be that by being careful.

The anti hydroscopic (moisture absorbing) properties of silicone are not worth the effort..........Instead of holding moisture in suspension to be readily flushed out at the next bleed....it still gets in through humidity/condensation and forms little globules of water....which then rust the cylinders ar other components......

Just use a good quality fluid and replace it every 3 years and you'll never have a drama.

 

Interesting....I was told by a fellow in who sells all kinds of automotive fluids and such, told me under no circumstances should the 2 fluids be mixed. He also told me that the only way to be sure is to replace most of the larger components in the system, like calipers and master cylinder. He did explain to me why this needs to be done, but for the life of me, I can't fully remember what he told me in a way I would be able to explain it here.

I will try to reasearch this some more. Because now I want to know what the true story is on this.

 

Silicone brake fluid and conventional, glycol brake fluids are compatible, however, they are not miscible. In other words, they can both exist in the same system with no harm being done but they will not mix.
That being said, the system will only be as strong as its weakest component. Therefore, if any glycol fluid remains the entire system will behave like a glycol filled system with its lower boiling point and high moisture absorption.
The only way of insuring that all the glycol is out of the system is to drain it, flush with alcohol to remove any traces of glycol, then flush with nitrogen to remove all of the alcohol.
I feel that the only reason someone should go through the trouble of switching over is in the case of a museum - displayed car. The silicone will not aborb moisture and thus will not allow corrosion to occur within the system.
That's my story and i'm sticking to it.

 

Non- hydroscopic fluids like silicone will force any moisture out of the system as beads of water. All brake systems get contaminated by water after a while, that's why racers change fluid so often. If you are tracking the car the last thing you need are beads of water showing up at the calipers. H2O boiling point-212 F. Temperature at calipers after a few hot laps-over 300 F. Guess what happens when that water near the calipers turns to vapor at 212. Goodbye braking system. Very dangerous for track use, recommended (as posted below) for show cars. If you drive hot on the street you may have the same problem.

Just curious why you didn't go with a DOT 4 high temp fluid like NEO, Castrol SRF or ATE?

 

Sorry to pick nits, but...

It's hygroscopic, not hydro. I know, hydro means water, etc. Common misunderstanding.


Best regards,

Rob Schermerhorn