Brake pads are good, rotors are good and everything else checks out.

Randomly when I stop fast whether I'm doing it on purpose or coming down an incline. Right about when I am completely stopped I feel and hear a grinding/gurgle/scrape noise. It comes from the rear or below the rear seats.

If I had to describe it. It sounds like maybe the brakes are slipping. I know that's not the case but what the hell is it?

Driveline noise? I'm confused.

ABS/ ATRAC kicking in when it shouldn't? IDK how familiar you are with those sounds but thats my first thought. I don't know what sensors it would be. Do you get any lights on the dash?

Maybe the slip on your driveshaft is grinding while compressing? Trying to think outside the box, it's right under the rear seats

That's what I thought it would be too. Either one of your suggestions. No lights on the dash when it happens either. It doesn't stop me in any way from slowing down besides making the noise. And it's not consistent.

Yeah just throw some grease in there and see if that solves it. The other culprits may be axle seals or the hubs

I've worried about the hubs for awhile. 128k miles and im assuming they're OEM like everything else has been. I believe i've driven it a lot harder than the previous owners.

Ill check those and load the driveshaft up on some grease and see what happens. its been awhile since i've greased it.

Our 4runners have Electronic Brakeforce Distribution, so rather than have a proportioning valve they will use the ABS to balance brake force between the wheels. As a result the ABS might kick in sometimes even when it's not needed. If you have no load in the rear it's more likely to reduce rear brake force since those wheels have less traction. With a heavy load in the rear, ABS might come on in the front. I think it senses traction, not load, so it's more likely to happen on loose or uneven surfaces (some grit on the road could do it), just like normal mode ABS.

There's also Brake Assist which "helps" you apply the brakes if it thinks you need to stop hard. It seems to automatically apply maximum braking force, which activates ABS on all surfaces. To me it's annoying because it makes the brakes grab harder and more suddenly than they should.

thats some good knowledge right there.

Thanks

Not to thread hijack but that brake assist is a HUGE PITA, especially if you're towing a trailer. Ugh! Let ME put on the brakes please.

Did you ever solve?

similar grinding noise on my 04 rav4, none on the runner

Had a grinding noise on my front left when stopping hard it turned out to be a sticking caliper. Wouldnt really call it grinding tho it was more like a really loud moan that you could feel in the floor.

Think I have the same noise. Get worse as it gets warmer. 1st stop is quiet, 4-5 stops later and it's much worse with in city stop and go traffic. Pads are OEM and good, rotors are aftermarket, calipers are reman 2010+ and not locked up. I'm thinking it has to be axle/bearing related. Any other ideas?

ended up being the cheaper toyota brand pads that they stopped making.