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jfh
04-06-2006, 08:52 AM
After replacing or rebuilding the entire brake system on my 63 hawk, I now read an article in hemmings touting the value of silicon brake fluid, Anyone have any experience with the stuff or Am I just out of the loop? Everything I read says Dot 3 brake fluid . Any thoughts?
Thanks

Dick Steinkamp
04-06-2006, 09:55 AM
quote:Originally posted by jfh

Any thoughts?


From this group [:0]. (You're kidding...right[?])

;)




http://thenobot.org/images/s2d/s2d_01.jpg

kmul221
04-06-2006, 12:20 PM
I've used the silicon fluid in several of my Studes with no problems
(eg) premature brake light switch failure.It does not absorb moisture
so cylinder rust from sitting is less likely.A bit on the expensive side but worth the expense if you are going to keep the car.

N8N
04-06-2006, 12:21 PM
here's some light reading for you :)

http://groups.google.com/group/alt.autos.studebaker/search?q=silicone+brake+fluid&start=0&scoring=d&

nate

--
55 Commander Starlight
62 Daytona hardtop
http://home.comcast.net/~njnagel

garyash
04-06-2006, 12:38 PM
Oh, all right, I'll get the debate started. Silicone (with the "e") brake fluid versus glycol (DOT3 and DOT4) is a continuing argument fed by misinformation, bad practice, and a few useful "facts".

Silicone fluids will not absorb water and the others will. Water gets into the system through the master cylinder if the lid isn't sealed tight. There are probably a few other ways to get water in, because experience shows that it does get in. With silicone, it is alleged that the water will accumulate in a pocket or low spot in the system and cause rust. I guess with water absorbed into DOT3, you get rust equally everywhere. The fact is that brake lines rust out on old cars. Cars that sit for long periods tend to have more problems with pitted wheel cylinders than cars that get driven frequently.

All fluids are (almost) incompressible, so one fluid or the other does NOT give a more spongy pedal. It is necessary to properly bleed any system to get the air out to prevent pedal sponginess.

If you are driving your car very hard, the brakes heat up and can boil water in the brake fluid. Really hot brakes can cause the brake fluid itself to boil. Both effects can cause loss of braking power and spongy pedal. DOT3 boils around 400F, DOT4 boils above 446F, and DOT5 boils above 500 F. Unless you are driving a Stude Panamerica racer, there are very few of us that will ever encounter boiling point of the pure fluid as an issue. Silicone would win this one because its boiling point is higher. Note, however, that water in brake fluid reduces the boiling point substantially. Heaven forbid that my M5 should ever go fast enough and stop hard enough to boil my silicone brake fluid!

Here's my primary reason for using silicone fluid: it won't eat through your paint if you ever spill a drop or have a leak. Glycol fluids will.

Is it worth flushing DOT3 from an older car to put in DOT5 silicone? Probably not. You may encounter problems due to incomplete flushing and any residual alcohol used to clean or flush may attack the rubber parts or reduce boiling point. If you are completely rebuilding a brake system and are installing all new lines, new wheel cylinders, new master cylinder, etc., then you can choose which one to use. Otherwise, stick with what's in the car now. It's probably a good idea, especially on Studes that sit in the garage all winter, to flush the system every couple of years to get rid of accumulated water with either fluid type. Silicone fluids are more expensive than DOT3 or DOT4 glycols, which is probably why the car manufacturers don't use silicone as the standard fluid.

My comments are directed at Studebakers with drum or disk brakes. Newer cars, like those built with DOT4 fluid, may have other specific issues. Let the debate begin!

Gary Ash
Dartmouth, MA
'48 M5
'65 Wagonaire Commander
'63 Wagonaire Standard
www.studegarage.com

sbca96
04-06-2006, 02:59 PM
Dont forget about Synthetic .....:D;)

http://www.valvoline.com/pages/products/product_detail.asp?product=51

SynPower High Performance Synthetic Brake Fluid is recommended for ABS, hydraulic drum and disc braking systems and hydraulic clutches requiring DOT 3 and DOT 4 fluids. Its premium, synthetic, low-moisture formulation provides superior anti-vapor lock protection. It has a high dry-boiling point up to 500F that reduces the risk of fluid vaporization and possible brake failure.

*Exceeds DOT 3 and DOT 4 specifications
*For most ABS, disc or drum brake systems
*High boiling point reduces risk of brake failure
*Compatible with conventional brake fluids

Tom

1963 Studebaker Avanti (http://hometown.aol.com/sbca96/images/63avanti.jpg), 102,000, custom made brake brackets to mount 1998 Mustang GT 4 wheel disc brakes (soon to get 13" Cobra front brakes, 2003 Mustang Cobra 17" wheels, GM altenator, will be getting : 97 Camaro Z28 tan leather seats, 97 Camaro Z28 T-56 6-speed trans, Ported 'R3' style Avanti heads with stainless full flow valves, 'R3' 276 duration cam w/chrysler solid lifters, shortened push rods, aluminum cam gear, Edelbrock AFB Carb, GM HEI distributor, 8.8mm plug wires, waiting in the garage.

Skip Lackie
04-06-2006, 05:53 PM
I endorse everything Gary Ash said. I have used silicone brake fluid in several of my collector cars for more than 20 years with absolutely no problems. The metal parts don't rust, and the fluid doesn't get muddy. If you have rebuilt the entire system, I would recommend filling it with silicone fluid, especially if the car is driven infrequently. Otherwise, stick with what you've been using. Rubber parts like brake hoses and wheel cylinder cups apparently don't take kindly to being exposed to different fluids.

There have been a number or reports that the brake light switches used on Studes and other cars of that era tend to fail more frequently with silicone fluid. I have not had that experience.

Skip Lackie

ROADRACELARK
04-06-2006, 07:56 PM
The stop light switches that are compatable with DOT-5, can be had at your local Harley Davidson M/C parts counter. They are a little pricey, but name something from H/D that isn't.
Dan Miller

Dan White
04-06-2006, 09:34 PM
Since redoing my brakes, that had jelled w/ DOT3 a number of years ago I have used DOT5 in my R1 Hawk with no problems except the light switch once. I got a new one from Ron Francis that sells a DOT5 compatible one. Good pedal feel and no jelling and screwed up calipers/pistons.

Dan White
64 R1 GT
64 R2 GT

Harv
04-06-2006, 11:30 PM
I ditto what Skip Lackie says about Silicone Fluid. I put it in my '50 Starlight Coupe in '94 when I installed new lines, hoses, master & wheel cylinders. 7,000 miles later, no problems and no brake light switch problem either. I bought a '64 GT R1 Hawk last May and am not going to convert to Silicone unless I plan to replace all fluid components (not in my immediate plans). Just my 2 cents worth.

Happy Cruising All [8D]

StudeBakerHarv

DEEPNHOCK
04-07-2006, 07:00 AM
Silicone compatible, low pressure contact, brake light switches are also available from Ron Francis Wiring at:
http://www.ronfranciswiring.com/
In particular: http://tinyurl.com/j7bcr
http://www.parts123.com/parts123/yb.dll?parta~showpic~Z5Z5Z50000278a~Z5Z5Z5AAAJW~Z5Z5Z51~Z5Z5Z5~Z5Z5Z5
Jeff[8D]



quote:Originally posted by ROADRACELARK

The stop light switches that are compatable with DOT-5, can be had at your local Harley Davidson M/C parts counter. They are a little pricey, but name something from H/D that isn't.
Dan Miller

sbca96
04-07-2006, 04:03 PM
quote:Originally posted by ROADRACELARK

The stop light switches that are compatable with DOT-5

Synthetic is compatible with all fluids .......

If you have a Lark with swinging pedal, or Avanti, its SUPER easy to
just install an electic stop light switch, works considerably better
then the hydraulic pressure one.

Oh .. did I mention Synthetic?;)

Tom

DEEPNHOCK
04-07-2006, 06:28 PM
Be careful here when talking about synthetic, and silicone brake fluid.

Yes, synthetic DOT-3 and DOT-4 is compatible with non-synthetic DOT-3 and DOT4, but it is NOT compatible with DOT-5 (silicone) brake fluid.

Some interesting reading is here:

http://groups.google.com/groups?q=Is+synthetic+brake+fluid+compatible+with+other+brake+fluids%3F&hl=en&lr=&rls=SUNA,SUNA:2005-51,SUNA:en&sa=X&oi=groups&ct=title

http://www.findarticles.com/p/articles/mi_m3102/is_9_123/ai_n6221217
http://www.adlersantiqueautos.com/articles/brake2.html
http://www.shotimes.com/SHO3brakefluid.html
http://www.valvoline.com/pages/products/product_detail.asp?product=51

Just food for thought.
Jeff[8D]


quote:Originally posted by sbca96


quote:Originally posted by ROADRACELARK

The stop light switches that are compatable with DOT-5

Synthetic is compatible with all fluids .......

If you have a Lark with swinging pedal, or Avanti, its SUPER easy to
just install an electic stop light switch, works considerably better
then the hydraulic pressure one.

Oh .. did I mention Synthetic?;)

Tom

sbca96
04-07-2006, 08:52 PM
quote:Originally posted by DEEPNHOCK
synthetic DOT-3 and DOT-4 is compatible with non-synthetic DOT-3 and DOT4, but it is NOT compatible with DOT-5 (silicone) brake fluid.


Thanks for catching that .. I was answering two separate questions at
work (sneaking it in) and I failed to break them up better. Synthetic
is not compatible with silicone. Synthetic is a better alternative
then going with Silicone, since it has the benefits of Silicone, but
not the drawbacks (stop light swtiches). If you choose to go with a
Silicone blend, then if you have a swinging pedal Studie, the change
to an electric switch is quite simple.

Tom

studebakerkid
04-09-2006, 08:26 AM
I have used all three DOT 3, 4, and 5. In my Studes since I drive them regularily I use DOT 3 or 4 but for my nephew in his 68 Cougar I used DOT 5 simply because I knew that it was only going to be driven occasionally and hard on those occasions.

In any case when I rebuild brakes I apply silglide liberally. I am still driving with brakes that I did some twenty years ago due to the fact that I use liberal amounts of Silglide and it keeps the rubber parts pliable and the wheel cyllinders from rusting internally.

So for a daily driver I would not use DOT 5 but for a trailer queen you bet.

If you car is ugly then it better be fast.....

65 2dr sedan
64 2dr sedan (Pinkie)
61 V8 Tcab
61 Tcab 20R powered
54 Champion Wagon

curt
04-09-2006, 10:14 AM
I know people who have had DOT 5 'lock up' the wheel brake cylinders as does DOT 3 at times. I'm a DOT 3 man my self, each makes his nest on this subject.

GTtim
04-09-2006, 12:20 PM
At least one vendor that rebuilds Hydrovacs has told me that they do not think that the silicone fluid is compatible with that unit. I am not sure what the latest thinking is on this subject. Would anyone care to comment on their success or lack of it in this regard?

Tim K.
'64 R2 GT Hawk

Dan White
04-09-2006, 03:13 PM
I have been using DOT5 in my GT's Hydrovac for about 9 years now and no problems.

Dan White
64 R1 GT
64 R2 GT

studegary
04-09-2006, 06:51 PM
quote:Originally posted by GTtim

At least one vendor that rebuilds Hydrovacs has told me that they do not think that the silicone fluid is compatible with that unit. I am not sure what the latest thinking is on this subject. Would anyone care to comment on their success or lack of it in this regard?

Tim K.
'64 R2 GT Hawk


I think that silicone fluid MAY be compatible with a Hydrovac, but it is recommended to NOT use silicone in power brake applications because if you get a leak to the vacuum side, the silicone does nasty things to your engine.

Gary L.
1954 Commander Starliner (restomod)
1959 DeLuxe pickup (restomod)

Blue 15G
04-09-2006, 08:57 PM
Took the '54 out for a cruise today. Was driving on secondary roads and a pickup was following me closely for awhile. I pulled over to let him pass and he pulled over too. He told me my brake lights weren't working. I thanked him for this "good samaritan" gesture.

Point is, my car has regular DOT 3 brake fluid. So it just shows that the switches can fail eventually anyway, no matter which type you use. :(

As an aside.. when this man first walked up to my car, he said: "Nice Studebaker! It's a '54, right?" Wow, he not only correctly identified the CAR but also got the YEAR right! [:0]