Brake pedal abruptly started buzzing/vibrating at 3,000 miles *video*

[engineeer]

I tried bumping an older thread on the subject, but that didn't get any traction. I've searched quite a bit and I haven't seen any resolution to the issue. Some people seem to think it's the brake booster master cylinder, but nothing conclusive that I've found.

Here's a video of the noise. Please note I am not referring to the "wet shoe" noise that you hear in the video that all 5th gens have. This is a distinct buzzing noise and vibration in the pedal.

You hear it at 0:03, 0:10, and 0:15--might need to turn the volume up a bit. The vibration of the pedal is much more annoying than the buzzing noise.



It didn't do anything like this in the first 3,000 miles, then started happening constantly. It's been about 300 miles since this started and it's still happening non-stop. Anyone else experience this? I have an appointment with Toyota on Wednesday, so I'll keep this thread updated with what happens and the resolution.

Edit: forgot to mention that the only requirements for this to happen are that my 4Runner be on and me pressing the brake. It doesn't matter if I'm in park, reverse, neutral, drive, moving fast, moving slow, or not moving at all.

Update: brakes stopped vibrating the morning I took it to the dealer. They inspected it and couldn't recreate the problem, so they gave it back to me. It's been about 100 miles and it still hasn't done it again.

 

[BlackWorksInc]

That's the pump kicking in to top off pressure in the accumulator because you used up reserve pressure by pressing the pedal a couple times. Have you not noticed this in 3,000miles of owning the vehicle, it's pretty normal for them due to the hydraulically assisted system vs. traditional vacuum assisted systems older vehicles used.

It's normal for it to kick in for up to about 30~60seconds on start up, afterwards it'll usually pop on for a few seconds after depressing the pedal a couple times to top off pressure. I mean let the dealer look at it, maybe it's cycling a bit more often than it should; but based on the video you showed it seems to be about right.

 

[1engineer]

That's the pump kicking in to top off pressure in the accumulator because you used up reserve pressure by pressing the pedal a couple times. Have you not noticed this in 3,000miles of owning the vehicle, it's pretty normal for them due to the hydraulically assisted system vs. traditional vacuum assisted systems older vehicles used.

It's normal for it to kick in for up to about 30~60seconds on start up, afterwards it'll usually pop on for a few seconds after depressing the pedal a couple times to top off pressure. I mean let the dealer look at it, maybe it's cycling a bit more often than it should; but based on the video you showed it seems to be about right.

Yep. Every 5th gen I've had does this. Won't do it unless you pump the brakes frequently. Oh, sometimes it does it on start up.

 

[engineeer]

That's the pump kicking in to top off pressure in the accumulator because you used up reserve pressure by pressing the pedal a couple times. Have you not noticed this in 3,000miles of owning the vehicle, it's pretty normal for them due to the hydraulically assisted system vs. traditional vacuum assisted systems older vehicles used.

It's normal for it to kick in for up to about 30~60seconds on start up, afterwards it'll usually pop on for a few seconds after depressing the pedal a couple times to top off pressure. I mean let the dealer look at it, maybe it's cycling a bit more often than it should; but based on the video you showed it seems to be about right.

I have never noticed it in 3,000 miles of owning it and this is something I would have definitely noticed before. To clarify, it's not the noise that I notice as that's not audible when I'm sitting normally even with the radio off. It's the strong vibration in the brake pedal that was never there before.

It almost feels as though something is leaking. Now that I think about it, the brakes do feel a bit mushier and the pedal travels a little further than before.

 

[engineeer]

Yep. Every 5th gen I've had does this. Won't do it unless you pump the brakes frequently. Oh, sometimes it does it on start up.

Mine does it on every startup--10 of them in total since this started. When the car is sitting there doing nothing (e.g. in the video), it will do it every other brake pedal press.

When driving around normally, it does it on almost every single brake pedal press no matter how hard or light I press the brakes. Sounds like maybe the vibration is normal, but the frequency and strength isn't?

 

[BlackWorksInc]

The frequency does sound a bit high... every other press or so is fairly normal. Let us know what the dealer says. Anything is possible I suppose.

 

[engineeer]

I drove home last night and the buzzing/vibration was the worst it had been. Woke up this morning to drive it to the dealership for my service appointment and, as luck would have it, the vibration issue was gone.

The buzzing noise is still there if you listen very closely with the radio off (non-issue), but the brake pedal vibration (the thing I noticed starting on Saturday) is completely gone. I dropped it off at the dealership anyway and explained the problem to them, so they're going to poke around and see if they can figure out what was causing it in the first place.

Will report back once I hear from them.

 

[dedonderosa]

keep us posted my buddys 16 quicksand trdp is doing the same thing its like every few pedal depresses. when i drove it its very annoying and i have never had any car feel like that

 

[makeyourself99]

Hey everyone,

Did anyone ever get to the bottom of this. My 2016 4runner is doing the same thing and it is extremely annoying. It feels like a click when I press the brakes and then I can hear the elctronics....it happens very often

Thanks