mhzmike6

Hello everyone. First post here. I bought a 2017 Honda Civic in October 2017 and for the past two to three weeks it has been making this repetitive thumping sound whenever I brake at speeds above about 35-40 mph. It sounds like a rabbit smacking his foot on the ground if you know what that's like. I think it is coming from the brakes. It only happens when I brake. I'm hoping it's normal cause it is a new car, maybe, the ABS I was thinking. If I have the radio on you won't notice it if you've never heard it. But, I don't really know what it is and it is driving me crazy. I'd like to add that the thump is extremely mechanical in repetition. It starts out fast and then as the car slows down the sound repetition slows down and transitions smoothly. It's like a robot hitting a drum in fast repetition at first then quickly spreading its beat out until it stops.

ezone

What did your dealership service department say about it when you took it in to them to get it fixed under warranty?













My guess: Lot rot.

The car sat for some period of time without driving after it rained or got washed, the pads rusted against the brake rotors and now that rusted spot in the rotor causes the thump every time it goes around with the brake applied.

This can happen in just a couple days if the conditions are right (or wrong).
The rust spot(s) are in the shiny surface of the rotor, may have the shape of the brake pad and may only appear as a discoloration and outline depending on how much surface rust has been taken off by driving it...... the spots may be visible on the outboard side of the brake rotor, or it may only be on the inboard side and hard to see without some work and effort.


We call that "lot rot" because it's a frequent occurrence on cars that sit on the car lot for long periods of time.
It happens in your driveway, garage, at the airport, parked on the street, etc.

New, used, this brand, another brand, it doesn't matter just about any car can have it happen.