ignatz

I backed my car up yesterday without noticing the emergency brake was set and heard a noise from the rear. I released the brake and it seems to work OK and the car rolls freely but it is difficult to tell if they are as effective as before in my driveway. I am wondering if it is possible that a lining permanently shifted. Also are these similar to the C3 mechanism which I am passingly familiar with?

Dano523

C6 E brake pad set up, and normal for it to make a little noise if you are trying to back up with the horse shoe pad engaged/lever still up. The shoe pad only hard contacts the adjuster bolts at the end of it, and there is a springs in the mix that hold it in place. So when you back up with the E brake still on, this shifts the springs that is holding it in place that is loaded for normal forward rotation, as well the shoe against the plate, and you get that funky noise with the spring clip position shifts in it retainer tabs on the plate/inside of the shoe pad, shoe moving to the other direction on the plate.




Also to point out, the E brake adjusters do not automatically adjust on their own. So to tell if it time to adjust the E brake pad adjusteres, pull up on the shifter and count the number of clicks where you can't pull the shifter lever any more.

If you can pull the shifter past 13 clicks, then its time to adjust the shoe adjusters.
8 clicks is a touch on the tight side, 13 clicks is too many, so about 8 to 11 click is a perfect setting (which allows you to use the E brake for E brake turns as well).

ignatz

I should have mentioned this is on a Z06, but I would bet the mechanism is the same. Thanks for the pix, this looks better than my C3 if I am visualizing it correctly. That brass colored ring is one piece with two linings attached and opens and closes with the parking brake lever. The spring, if that is what that wire thing is, is to keep the brass ring closed against the brake mechanism. It's not clear to me what that wire does. Maybe it is just tension in the brass ring and the wire does something else? Seems like a better design. It must be robust enough to stop the car with the wheels turning some without damage. It sure works better than my C3.

In my imagination I figured the brake lining was just moving radially, there really isn't anywhere else for it to go nor anything obvious that would break or get displaced. The e-brake seems OK but you've inspired me to check the adjustment.

torquetube

The spring wire just keeps the brake shoe away from the side of the drum when released, and from rattling around.

Dano523

Closes, the gold part with pad is the Shoe itself, and its spring tension'd to hold it self tight against both sides of the adjuster.
The wire part is the keeper of the shoe to hold it tight to the plate alone.

So when you release the E lever, the shoe itself will shrink down, and this semi centers the shoe inside the rotor drum section. When you pull the lever, it expands the shoe to bite into the drum part of the rotor.

Since the E brake does bump against the drum a touch even when it shrink back down via forward rotation of the rotor, the shoe will always be semi clocked towards the front car side on the plate. With the e brake on, and trying to go backwards, this causes a shift of the shoe on the plate towards the back of the car tight against the rotor drum surface, and this is the noise that you where hearing.

Hence shoe against plate, spring keep wire against plate and shoe, and a slight shift of the end of the shoe against the adjusters as well.