Low rumble/groaning noise when come to a slow stop

Question

I just replaced my front brake pads and rotors about 2 months ago and am now hearing a very noticeable noise when braking. I'm driving a 2010 Honda Civic LX-S with about 67K miles.

The odd thing is that it only appears when coming to a slow stop, not hard stops. I've had a Honda mechanic drive my car but since the noise didn't happen when he drove it, he says everything looks good. However, this morning it was awful. I heard it the whole way to work and it seems to be getting worse.

Any ideas what it could be? I'm by no means a mechanic, I have always had my dad fix car issues for me but he lives 500 miles away now.

Answer 1

I had a similar issue on my truck. What I found was the caliper was not moving correctly and the pad was wearing unevenly. One side of the caliper was stuck, so was causing the issue. For my truck, there is a rod which the caliper attaches to. This rod had rusted and was not allowing free movement. This caused the brake pad to wear unevenly and cause the vibration.

I'm not sure how your Honda's brakes are put together, but your mechanic should be able to see if the pad is wearing unevenly. He would have to take it apart to do so. Since the rotors/pads are brand new, there might not be much visible wear on either. By taking it apart, it may become self evident what the issue is.

Answer 2

As noted in the comments, it can be difficult to diagnose from very little information. However, some things worth considering:

• Disk brakes have one or (more usually) two springs between the brake pads and the calipers: the pads move along these springs when in use. If they have been installed in an incorrect position (or even omitted - have seen that), that would certainly explain some vibration. This vibration will be felt mostly when the brakes are in light use, as reported by the OP. This should be easy to spot with the wheels off.
• The OP notes the disk rotors have also been changed. Have quality parts been used (i.e. made by the original manufacturer)? Have they been torqued up in a correct star pattern? The vibration at low braking force is also consistent with disks that are slightly off true, causing the pads to connect and disconnect repeatedly when braking slowly. When braking more strongly, caliper pressure will force the pads into continued contact with the disk, so vibrating much less if at all.

HTH

Answer 3

Not sure what springs @Alan Ward is talking about? Maybe he's referencing the brake "hardware" that the ends of the pads are set into that should be replaced when performing a brake job. The caliper is operated by hydraulic pressure (a.k.a. brake fluid) to move one or two piston cups that press against the inner brake pad that in turn presses against the rotor to stop the vehicle.

From what you stated, it sounds like a low rumble/groaning. The first thing that I think of with that description is that it could be the wheel bearing on either the driver and/or the passenger side and not the brakes since it would have been making that sound almost from the get-go after the brakes where done 2 months ago but again I'm only going off your description details.

Since you said that you are not mechanically inclined, I'd suggest having the wheel bearings and brakes checked by someone other than whomever did your brakes 2 months ago (to get an unbiased opinion).

Hope this helps and please let us know what you find out so that it might benefit someone else with the same problem.

Answer 4

A sticky caliper pin or misaligned brake pads could be the reason.

This guide is quite helpful:

https://www.autocornerd.com/groaning-noise-when-braking-at-low-speed/