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Hey all. I had a nasty little suprise from my Polly yesterday. I got to the bottom of a hill, started slowing down, and then right before I REALLY needed to stop, my brake pedal went stiff, wouldn't stop my car! I grabbed the emergency brake about a half-second too late and ended up rear-ending the car in front of me. There wasn't too much damage, just a dent in the other car's bumper (it would be a 2009), but it scared the #@%! out of me. The brakes seem to be working ok now, but I'm scared to drive her again until I know what the problem is. Any answers?

I had the rear shoes adjusted too tight and going down a steep hill and constantly using the brake gave me severe brake fade. I was standing on the brakes but had a tough time stopping. The lining made today just doesn't perform as well. The dummy who had adjusted the brakes went over them again and I haven't experienced the problem again.

If you have the Easamatic, it sounds like the vacuum portion failed-- either stuck check valve & no vacuum or something inside the power cylinder. Anything failing in the hydraulics generally results in no pedal & all the way to the floor. If not power brakes, then also open to suggestions.

I do have the Easamatic brake system. My shoes are all in good order with plenty of pad left. I'm thinking that the system ran out of vacuum?

I don't know how steep the hill was or how much braking you applied before you had the problem, but most drivers today are completely ignorant of the old adage, "if you need a reduced gear to go up a hill, you should use the same gear to go down". What you experienced was either of the two things already mentioned, loss of vacuum boost, or just plain old simple brake fade which could be caused by the shoes being adjusted too tight. Also different types of lining materials have different resistances to fade.

Even though I have auto transmission, I gear down anyway. I think doing this helped everything turn into a minor fender bender (I think I was travelling all of 3 or 4 mph), still, scary! I guess I'll be driving with my hand close to the emergency from now on....

Check brake shoe adjustment.

I'm not sure what 'brake pedal went stiff" means. Does that mean it would not move at all from the rest poistion or does that mean the pedal went down a little ways (as normal) and then became hard??????

It went down a little way and then was stiff as a board, no grab at all no matter how hard I pushed on it. I probably damn near bent the pedal!

I'd have a look at the check valve. Seen a few where particles of rust had accumulated inside. All it takes is one flake in the right place to prevent the valve from sealing.

If not a vacuum failure, sounds just like plain and simple brake fade. If it gets bad enough the fluid will boil in the wheel cylinders and the pedal will drop to the floor, which many people mistake for a master cylinder failure. After the fluid cools the vapor phase recondenses and everything is normal again.

Brake fade when subjected to heavy braking and overheated is not uncommon with drum brakes, when I learned to drive, instruction on how to cope with it was part of driver education. Some things can exaggerate it; incorrect wheels which restrict air flow to the drums, excessive layers of paint on the drums inhibiting cooling, inferior linings (try metallics).