Truck going to shop Wednesday but wondering if the forums can help out. Brakes abruptly make horrible crunching noise when coming to full stop only. That is, decelerating will be fairly normal, only the actual stop elicits a very jerky motion and loud sound as it there are pebbles between pad and rotor. Wife claims didn't hit anything or drive over sketchy surface. Happens now with every stop. Mechanic thought anti lock brakes but not symmetrical thud thud thud. Just racket like literally something caught in brakes / wheel when stopping fully but nothing I can see. Truck quiet at speed. Thoughts? Thanks

Have you had a wheel off to take a look? Otherwise it's all guessing.

Well if your wife drives it alot the pads are probably worn down.

Pads, not rotors changed out 30k ago at around 60k. OEM pads. Truck has 100k now. Didn't take the wheels off yet. I just walked around / crawled under. Nothing obvious to my untrained eye. No dummy lights on console. Just thought I'd ask on here in case anything notorious. Doesn't seem like seized calipers on these 5th gens vs the 4th gens. Also checked parking brake but don't think that's it even though my light only works intermittently because noise only happens going to full stop...

Wheel bearing?

indicator tab?

My guess would be pads/rotors considering the noise is braking dependent. A wheel bearing could also be the culprit but you’d have a drone/vibration at speed as opposed to a jerking stop.

I’ve seen times when the wear indicator tab on the pads will completely break off, bringing you down to the bare metal on the backing plate.

My thoughts for your issues: The jerking motion you mentioned is usually a case of warped rotors. The crunching/grinding, usually pads down to the metal backing plate.


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I'm going to throw this out there just in case.

I have a Scion xA. It was making a sound as I came to a stop that sounded like grinding wheel bearing(s). Took it to a local shop who, using a stethoscope with the car on a lift, determined the noise to be coming from a bearing in the manual transmission. They didn't work on transmissions, so I hunted down a place that does.

Short story is that they traced the noise to a tire. They were right. They replaced the two front tires, quiet as a mouse. In my case, there was a severe bump in the road that I traveled every day that must have caused some separation in the belts.

Unlikely, but thought I'd share.

Always thankful for the knowledge on here. Was the obvious. Pads worn to metal hitting rotor. First set of pads lasted 60k, second set only 40k. Both OEM pads. maybe the rough rotor surface accelerated the wear? Or maybe wife just heavy on brakes...

That's quick wear for pads, in my experience. Everyone drives differently. Glad you got it figured out!

A few thoughts.

I'm assuming it's a 4runner - which model and year? There have been a number of posts on (Trail/TRD Off Road) KDSS Failures. Apparently that sounds more like a clunk though, but you never know until it's checked.

ABS activation sounds like a winding ratchet spring, buzz, clack, clack, clack. If the ABS controller is going out the ABS will kick in super early and you will feel the pedal goes dead. You will know if this happens, because it's like driving on ice and super freaky. You will be like WTF was that?? This happened on my Tacoma - Note it's not cheap to fix.

If there is a failed or stuck component it will usually pull, shimmy, leak or smell bad. Unless you have those symptoms, it's likely something else.

Brakes don't last any specific mileage. I've had brakes last 10K and 50K. It depends on the material and what you do with them. So 30K miles is not outside the realm of possibilities.

The pads might just be worn unevenly. If they are thinner on one side they can do strange things. This happens for a number of reason.

The pads could just be metal on metal it will make a grinding sound. Occasionally the squeakers break and you won't hear anything. Grooved rotors are usually a sign.

Total shot in the dark here. There could be debris between the pad and rotor. It's unlikely on the 4runner as it's has enough space to let stuff out, but this used to happen to my Audi all the time (freakin precise German engineering). Just for giggles I would power wash the rotors. Just stick it in, through the wheel, and have at it. It could just be some dirt embedded in the pad.