I have read here that the early cars 20-21 had the brake pads glued to the caliper pistons. (?) That never made sense unless it was to keep the pad retracted while driving.
My 2023 Z51 did not have glue on the pads/pistons. I switched to PowerStop pads after 4000 miles to keep the dust down.

8000 miles now and I hear the pads dragging sometimes. Not all of the time, but sometimes after a corner or curve in the road. Tic tic tic tic tic. If I step on the brake pedal it goes away for a while, sometime comes back.

Clues at the scene of the crime: I have drilled rotors, and aftermarket wheels with +18 offset.
The offset wheels put more pressure on the wheel bearings, the drilled rotors probably make more noise than a stock rotor.

Is that common to hear pads dragging, or do I have a sticky caliper piston? Or some other issue. It appears to be on the front, but I cannot tell if it is left or right.
PS. I put on a new set of drilled rotors recently. It helped some but I still have the problem. Sometimes I drive for 15 minutes and do not hear it. Then it starts.

 

^^^^
Double Sided Brake Tape, commonly used in Europe, are to reduce vibration and noise not to pull pads back. It was on my early 2014 C7 Z51 and my 2020 C8 Z51. PIA to remove Pads. Easier to remove my removing the caliper. BUT that is harder to do!

I and others found ways to remove with pads with calipers in place. None of the low dust street pads used that tape. BTW later 2014 Z51 did not have the double side brake tape, like the C8.

I switched my 2014 C7 Z51, 2017 Grand Sport and C8 2020 Z51 to Carbotech 1521 street only pads. Stop great when pads are at ambient and at the max temps they recommend for these Street Only Pad. They are NOT for Tracking. Never heard any noise with all three.

 

I've used something similar to this to quiet disk brake noise:
https://www.autozone.com/greases-and...4oz/348169_0_0

It basically glues the brake pads to the calipers/pistons.

But it wasn't a tic tic tic noise. Usually it was a squealing noise on light brake application. And, in theory, it isn't necessary for pads with shims but I've used it successfully to get rid of noise on pads with shims.

I thought I saw a post from someone with a ticking noise that was cured by following a TSB that called for cleaning the interface between the wheel and hub.

 

I have used something like that "grease" that is almost like a silicone that sticks to the pads and pistons.
Like you said, it cures a (high frequency) squeal when stopping.

I have heard of the wheel/hub problem also.
My issue is definitely the brake pads dragging. They don't squeal when I stop, they drag when driving. Not all of the time. But it is a brake pad sound.
When I hear the noise and hit the brake pedal the sound changes to a constant friction sound. Or I just tap the brake pedal and the sound stops or is way less.

New rotors made a difference but did not cure the problem. I have Powerstop pads, I'm thinking of trying a set of Carbotech.
It has to be rotors, pads or calipers.

 

Have you checked the runout of the rotors? Perhaps a combination of rotor runout and drilled rotors catching an edge of the pad. It seems strange that a pad would cause a tic tic tic noise.

 

Check the Runout.. I guess that would be the next step. That would be important in any diagnosis.
It was wishful thinking on my part that drilling the rotors would not cause any warp, but that could be the whole problem.
The drilling does not go all the way thru. I just used a center drill and went .280" deep. Drilled 30 holes front and back of each. It sure looks cool, but that could be the problem.

 

It looks like you didn't put a chamfer on the drilled holes. I could envision the edge of the brake pad catching on the hole edges causing a clicking sound.

 

PROBLEM SOLVED: Thanks to everyone for your input.
I kept listening and hearing this scuffing noise, not all of the time, kind of unpredictable.
I am thinking it is not the rotor, or it would be making noise all of the time. It has to be a sticking brake pad, or sticky piston in the caliper.

It seems to be coming from right front, sometimes I hear a similar noise left front. Z51 with Powerstop pads.
I removed the front pads to see if there was any reason they would be sticking.

The pads are extremely close tolerance to the opening in the caliper. I was surprised that there is very little gap on the ends.
Usually pads have room to rattle around, these are very precise, and a close fit.
There was a small burr on the end of the steel plate. You can see when the steel was stamped and it left a small burr.
Is that what is making this pad get stuck in the caliper and not retract?
I hit this with a file so you can see it, but the burr is still there.


After. No worries about taking off too much metal. There is an anti- rattle spring at the top of the caliper
I just cleaned it up so there is no sharp corner for it to hang up on. Basically took off the paint and a little bit of metal. Put on a generous corner radius.
Test drive. BINGO. No noise. I'm back in the race. Can't wait to get out and drive while there are good days left.

These pads are manufactured to such a close tolerance that one little burr on the edge caused the pad to stick in the caliper. I'm surprised that this has not happened to more people.
Maybe the drilled rotors make more noise so this stands out on my car.