I have had silicone brake fluid in my '57 T-Bird for many years. Put in new wheel cylinders and master cylinder at that time. Had Power Brake booster rebuilt and installed stainless lines also. Had a little problem with leaking fittings at first but stoped the leaks by retightening the fittings. Had to have the boster rebuilt after several years again. Had to replace the brake light switch last year but it had been in there for many years. My experience is that it is well worth the trouble. It is a little more difficult to bleed the system. Peddle seemed to be a little mushy at first but that went away after a little while.

I have been running silicone (Dot 5) in my 48 ford for 20 years and never had any leaks. Did have some problem with the hydraulic stop light switches, went to a mechanical switch.

54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

what happens to the brake light switch?

"God Bless Texas"location: Houston,TX

I am changing back from silicon to conventional. Silicon leaks past the wheel cylinder seals, makes replacement of the brake light switch mandatory on a yearly basis. As far as I can see it buys me nothing.

From the description of the fluid, it sounds like it's contaminated and needs to be changed out.  Dot 5 fluid does a good job of staying clean over the long haul if not mixed with any other specification brake fluids.  Flushing the system and insuring all the old fluid is out of the system before refilling it would be prudent.

Lorena, Texas (South of Waco)

If it is not siclicone, I would switch to it.

Dot 5 is usually purple

54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

Put some fluid on a flat surface, and put a couple drops of water on the fluid.  Silicone won't accept the water, it will bead up like on a freshly waxed hood.  Glycol fluid and water will tolerate each other, actually mix if left sitting a while.

John - "The Hoosier Hurricane"

duh!  well my nose was right in front of my face on that question!!

consider me humbled!

"God Bless Texas"location: Houston,TX

DOT 5 won't strip paint - test in an inconspicuous area.


Lawrenceville, GA