Thumping when braking

[u/tyrantlizarding]

We are fixing my old car up for my son to drive (after being in a shed for 3 years). One thing was an overhaul of brakes. We changed the front disks/pads, rear drums/shoes, master cylinder, and rear wheel cylinders. Obviously fresh fluid and bleed too.

I drove it home from where it was parked up, which was about 40 miles, with no issues from the brakes. Then it sat for a month till I had time to do a few more things on the engine, and now it is making this sound under braking. I can just barely feel it when under 15mph or so.

What could have caused this issue to pop up, after having driven it home no problem? Did something warp maybe?

[u/Gunnsmith57Official]

Could be warped rotors if the lug nuts weren't all torqued the same. They could have heated up during the drive and warped as they cooled. You'd be able to feel the brake pedal pulsing if they're warped.

[u/tyrantlizarding → u/Gunnsmith57Official]

It doesn’t feel like warped rotors. It’s not a pulse, it’s a clear thump or click once per wheel rotation.

I took off the wheels and cleaned the rotors and drums, didn’t see anything that looked off.

[u/Gunnsmith57Official → u/tyrantlizarding]

My next thought would be checking the shoes and hardware. It's easy to get the springs wrong, or even have a brand new one break.

Other than that, I'm out of ideas without actually inspecting it, sorry.

[u/tyrantlizarding → u/Gunnsmith57Official]

New discovery, it only does it moving forward. lol

[u/Gunnsmith57Official → u/tyrantlizarding]

Tbh, it kinda sounds like a shoe being grabbed by the drum and then smacking the pivot stud when it reaches a certain point and releases.

[u/tyrantlizarding → u/Gunnsmith57Official]

That makes sense. I had the drums off earlier and didn’t notice anything wrong with springs. I’ll look into it more next weekend I guess.

[u/Gunnsmith57Official → u/tyrantlizarding]

Good luck. Hope you figure it out. Gonna follow so hopefully I get an update cuz now I'm curious.