Silicone Brake Fluid

-
R

Rocket

FABO Gold Member
FABO Gold Member
Joined
Apr 22, 2005
Messages
3,006
Reaction score
966
Location
CT
I am in the process of rebuilding my Barracuda brakes and remember back in the nineties there use to be silicone brake fluid. One of the beneifits was that the fluid never needed to be changed (or not as often) as it did not absorb moisture like conventional brake fluids. Given that I want my new system to stay as rust free and as new as possible for many years is this still an option? Has anyone had good or bad luck with this type of fluid? This would hopefully save changing the fluid every 2 years as a minimum. I have not seen this product in many years.

Thanks
 
It's DOT 5 brake fluid. Newer Harley's are useing it so it is becoming a little more common. You should be able to get it at any larger auto parts chain, if not Advanceautoparts.com (Partsamerica.com) should have it. It's not cheap. Make sure you don't have any of your old fluid left in the system. When I do my final one over on my '68's brakew system I'll be switching over... I'll be changing everything so I know I wont have anything left in my system (master, prop. valve, lines, hoses, wheel cyclenders, calipers). If I'm going through that much trouble I'm going with the stainless lines and putting the best fluid in it.
 
We have been using silicone fluid at the shop for years on the high end cars we build. You're system should be clean and free of any contaminants, including older dot3 fluid. You can flush the system with denatured alcohol first, just make sure you are dry when you refill with Dot5. For us, the major benefit was that it wouldn't take out a big buck paint job if we sprung a leak. I don't think any of my customers drive their cars to the limits of where their fluid would fail or not, so, I don't have an answer on that end of it. Just remember, it is harder to initially bleed a dot5 system, the stuff seems to be a bit thicker.

Revhendo
 
Got it in 3 of my cars and not one problem with it.

But as said the bleeding is not done the old way of pumping the pedal and then bleeder screw.

As pumping will make alot of small air bubbles and give you a spongee pedal.

I buy my silcone brake fluid by the gal. $49.00(cheaper the $8-9 small bottle) from Kanter in N.J.

Only car its not in is the race car.
 
When I switched my Barracuda over to front disc brakes over a year ago I also switched to silicone fluid.

I DID NOT change everything. I only changed a few lines, the master cylinder and the front setup to disc. I bled the system a lot, maybe wasting 2 bottles of the stuff, just to be sure it was all clean.

I've been told you have to change all your rubber parts and hoses etc.etc. I think that's BS. I didn't change any of that, just bled the system a lot like I said.

My system has been fine since and my brakes work fine, no problems.
 
there is a reason people have been told to change all of the rubber parts when changing over to dot 5 fluid. back in 1977 when the harleys first started using this dot 5 fluid we had a problem with the brakes over heating and actually locking up. we found that the master cylinder piston cups were swelling up becuase the rubber was not compatiable with the dot 5 fluid, the piston cup actually swelled enough to cover the fluid return port.the compound of the rubber was changed in 1978 to correct the problem. we also had a very few cases of the hoses swelling internally . there is a reason for the manufacures to recommend a specific product in their bikes-cars... not every bike made had the problem but we did have every bike of one specific model have the problem,,,,,enough of a problem that a recall was issued -across the board for all models.....any rubber parts made to the pre 1978 compound can react this way ....so you are taking a chance...especially if the parts are made out of country , not every manufacture changed the rubber compounds in 1978, only those that were using or planned to use the dot5 in the near future....I was personally involved in this back then, so this is not an opinion.......just the facts...i can probably find the recall notice if some one would like the proof.....
 
I'm going through my car from the ground up and that's why I'm changing everything. If I was just going to change over I'd change all the rubber components... after all how many of us have a list we go by saying at X many miles (or KM) or X many years change your brake hoses. I'm the type that would rather know it's all good and I won't have to waist the one nice day (that I have off) screwing with my brakes and not driving around making fun of kids with fart cans for exhaust tips.
 
changing all of the parts is the right way to do it, providing you dont use imported parts.... you have no way of knowing the compatabilty of the foriegn made parts. but at least you have the information and now know what to look for if you do have a problem,,,, a couple hints....do not shake the dot5, let it sit overnight before using it. pour it in the master slowly, any air in the fluid will not bleed out the calipers. we had so much trouble with this fluid we actualy made up a way to " reverse bleed "the system ... we actually pumped the fluid into the calipers and up to the master cyl. the dot 5 likes to suspend air in it, and it also attracts air...just like the dot 3 attracts water....i have had many of my bikes that use the dot5 ..and bleed the brakes every spring . you may find that it likes to leak out of the master cylinder cover also. not really leak but mine are always wet around the gasket.. it is great stuff for not screwing up your paint, but it does come with a cost....
 
Everything comes with a cost. Ask my Ex wife.
I actually purchased a dedicated power bleeder for my shop just for Dot 5. It works very well, but it is a costly option for the private individual in the garage. At home, expect to bleed a couple of times to get the air out.
 
You must log in or register to reply here.
-

Back
Top