Disk Brake Growling
Disk Brake Growling
Here are two photos of the front passenger brake pad/hub/rotor. Notice the groove worn in the hub by the pad. Whenever I brake lightly at low speed (less than 10mph) I hear a growling noise from that wheel area.
The groove is not very deep, but you can feel a bit of a ridge.
Should I be concerned about this?
1970 Cutlass - new reproduction brakes from Inline Tube installed March 2012, 5,500 miles driven.
The groove is not very deep, but you can feel a bit of a ridge.
Should I be concerned about this?
1970 Cutlass - new reproduction brakes from Inline Tube installed March 2012, 5,500 miles driven.
I'm not familiar with the parts that are used in this retro fit. Your pictures are pretty clear. I would be concerned. It might me an easy fix, but the first thing I would do is contact the vender.
If these are stock or stock like, I would think about a new set of brake pads, only because they are cheap. Maybe they have a bad run of pads, I don't know. This still doesn't answer the question though. The pad shouldn't be hanging that low to groove the hub. Good luck.
If these are stock or stock like, I would think about a new set of brake pads, only because they are cheap. Maybe they have a bad run of pads, I don't know. This still doesn't answer the question though. The pad shouldn't be hanging that low to groove the hub. Good luck.
The pad is coming in contact with the rotor hub, it's not supposed to do that. Are the pads the correct ones? If yes, two things come to mind, eventually enough metal will wear away and it will stop or you can remove some metal off the hub to clear.
Whoa! That's weird. Never seen that before.
Are you sure that your calipers are tight on the brackets, and that the brackets are tight on the spindles?
If so, I would wonder about a mismatch between the pads (which I assume are what is dragging along the hub) and the rest of the system.
If all else is good (and you're SURE it's good), you may be able to get away with grinding a 16th of an inch off of the metal at the bottoms of the pads.
- Eric
Are you sure that your calipers are tight on the brackets, and that the brackets are tight on the spindles?
If so, I would wonder about a mismatch between the pads (which I assume are what is dragging along the hub) and the rest of the system.
If all else is good (and you're SURE it's good), you may be able to get away with grinding a 16th of an inch off of the metal at the bottoms of the pads.
- Eric
Did you cinch the ears on the pads? That will lift them away from the hub and keep them tight. It is described in the Service manual. Basically you use large vice grips or channel locks and squeeze the little tab at the top and the bottom of the pad. In picture 1, the tab is to the left of the pin and should be sqeezed tight downward against the caliper.
Last edited by brown7373; Aug 7, 2013 at 02:52 PM.
The pads came with the kit, so I believe them to be correct. All the bits seem to be secure and tight. The bottom tab of the pad seems to be snug in the notch (abutment) of the caliper. In the relaxed state there also appears to be clearance between the bottom tab and the hub, which leads me to believe that contact is only being made when the brakes are applied. This is reinforced by the fact that the growl only happens when I apply the brakes.
Why a hard brake doesn't create a growl I cannot think.
The next time I visit the car I will have an assistant apply the brakes with the wheel off so I can see if there is anything going on, although without any rotation it may not show much.
If nothing conclusive shows up then I will take a bit off the bottom tab of the pad and see what happens.
Thanks guys.
Peter
Why a hard brake doesn't create a growl I cannot think.
The next time I visit the car I will have an assistant apply the brakes with the wheel off so I can see if there is anything going on, although without any rotation it may not show much.
If nothing conclusive shows up then I will take a bit off the bottom tab of the pad and see what happens.
Thanks guys.
Peter
Did you cinch the ears on the pads? That will lift them away from the hub and keep them tight. It is described in the Service manual. Basically you use large vice grips or channel locks and squeeze the little tab at the top and the bottom of the pad. In picture 1, the tab is to the left of the pin and should be sqeezed tight downward against the caliper.
To be clear on what I should do in cinching the ears, in the photo attached:
the front ear is circled in yellow,
the gap referenced in the service manual is between the two green lines, and should be 0.005" max.,
the direction I need to move the ear is indicated by the red arrow.
Same on the rear ear.
The service manual calls for using vice grips but I cannot see how I can get them in there to bend the ear down, or how positioning them as shown in the fig 5.111 would bend the ear down.
The idea of using a punch is mentioned above, using a wedge between the tab on the bottom of the pad and the hub. Is this safe, or could it deform the pad?
Thanks, Peter
the front ear is circled in yellow,
the gap referenced in the service manual is between the two green lines, and should be 0.005" max.,
the direction I need to move the ear is indicated by the red arrow.
Same on the rear ear.
The service manual calls for using vice grips but I cannot see how I can get them in there to bend the ear down, or how positioning them as shown in the fig 5.111 would bend the ear down.
The idea of using a punch is mentioned above, using a wedge between the tab on the bottom of the pad and the hub. Is this safe, or could it deform the pad?
Thanks, Peter
I have to admit that I've never had any success with the factory's channel lock method of bending the tabs. What I usually do is bend the tabs downward with a hammer before I install the pads in the caliper. This results in an interference fit of the pad in the caliper, which requires the application of a little force to get them in place. Actually, THIS is where I use the channel lock pliers - once the tabs are bent I use the channel locks to apply force parallel to the caliper mounting pin axis to squeeze the pads onto the caliper. Note that there is usually some trial and error to getting the tabs bent enough to hold the pads in place.
I finally was able to take a few days off and go up to Newport and work on my brakes.
The issue was as suggested above. The radial clearance between the pad ears and the caliper was almost 0.25 inch.
I wedged a small chisel between the rotor hat and the lower pad tab, and used a flat punch and hammer to bend the ears down.
The first couple of hits sent the chisel flying off across the garage, right past my face! I wedged it back in and secured it with some masking tape, essentially tying it to one of the wheel studs.
A few good hits with the hammer and the ear obliged.
I repositioned the chisel and had a go at the rear ear. The clearance was reduced more than enough to stop the pad moving radially in and rubbing on the rotor hat.
What I was not able to accomplish was to bend the ears laterally to stop the pad moving in the direction of rotation. You can see from the photos that there seems to be more than the 0.005” clearance in that direction. But the lower tab is nice and snug and I have never felt any chucking.
Thanks to all who helped, and thanks to CFHCAR for the suggestion to use the hammer and punch. I cannot imagine being able to apply enough force with vise grips to accomplish the job.
Lesson learned – make sure that the chisel positioned between the bottom of the pad and the rotor hat is tied down, otherwise you will have missiles wizzing by your nose.
Cheers, Peter
The issue was as suggested above. The radial clearance between the pad ears and the caliper was almost 0.25 inch.
I wedged a small chisel between the rotor hat and the lower pad tab, and used a flat punch and hammer to bend the ears down.
The first couple of hits sent the chisel flying off across the garage, right past my face! I wedged it back in and secured it with some masking tape, essentially tying it to one of the wheel studs.
A few good hits with the hammer and the ear obliged.
I repositioned the chisel and had a go at the rear ear. The clearance was reduced more than enough to stop the pad moving radially in and rubbing on the rotor hat.
What I was not able to accomplish was to bend the ears laterally to stop the pad moving in the direction of rotation. You can see from the photos that there seems to be more than the 0.005” clearance in that direction. But the lower tab is nice and snug and I have never felt any chucking.
Thanks to all who helped, and thanks to CFHCAR for the suggestion to use the hammer and punch. I cannot imagine being able to apply enough force with vise grips to accomplish the job.
Lesson learned – make sure that the chisel positioned between the bottom of the pad and the rotor hat is tied down, otherwise you will have missiles wizzing by your nose.
Cheers, Peter
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