A few days ago I noticed a systematic knocking sound coming from the back drive wheel area when braking and coming to a stop. The knocking is a faster rap if the speed I'm stopping from is faster and as I slow down the knock decreases in reps.

I took the wheel off the other day and inspected. Took the brake drum off and everything looked fine inside there...have decent pad left on the shoes.

The one thing I did notice is it looks like the 6inch of so sway bar end link that bolts to the frame forward of the hub...the grease boot is torn and there isn't any grease left inside. Could this be what I'm hearing?? Would this cause a repetitive type knocking? I assume these are just a remove and bolt back on fix and shouldn't be too hard to replace to narrow down if this is the issue.

Any other thoughts would be great.

Thanks!

 

Remove the sway bar links and test drive it (I don't have either of my swaybars on). If the noise stops, you found the problem!

 

So just take the end links that bolt to the frame out and let the swaybar hang loose!?

 

I would remove the links so they aren't banging around and the tighten the sway bar mounts to keep the bar in place. Or you could just remove the whole thing (note: it's tricky to get the sway bar out of there but if you disconnect the passenger side rear lower control arm from the frame mount, you can slip it out much easier). You might want to jack up the rear end and spin the tires to make sure the sound isn't a blown diff or anything in the axle.

 

I was thinking about jacking it up, putting stands under it and chocking the front wheels and running it in neutral or light acceleration and applying the brakes to see if I can reproduce the sound.

 

Not a bad idea, just be very careful and make sure those stands are solid or it could be dangerous!

 

Only other thing I could think of is one of your drums might be out of round.(due to heat then splashing through water?) also look for weird tire wear.

 

I'm hoping it is just the swap bar end link. I never taking it off roading. Any water it has run thru is regular rain and the tires are only around 20K miles onld and I religiously get them balanced and rotated.

I'm lazy and take it to the dealer for oil changes....if replacing the end link myself doesn't solve it...I'll ask them to give it a once over when I have the oil changed next...which it is due for.

 

Well, took it into the dealer yesterday for an oil change and have them try to diagnose the problem.
They said the self adjusting rear drums were not adjusting properly so they lubed and adjusted and sent me on my way.
Driving around last night the tapping/knocking was back!
Took it back in 1st thing this morning. 6 hours later they call and say it is the "rear brake kit" on both sides that is not working right.
They say they don't see this that often...they don't stock the parts...and it is $730 total to fix!!!

Had anyone seen or hear of this before? I have no idea what a rear brake kit is!? Is that the whole drum setup?

Really wasn't looking to spend $700 on the 4runner anytime soon!

 

They said it is the brake backing plate near the axle that is causing the noise. They said they made some adjustment to it as a temporary fix. They said to replace they have to take the hub off and take out the bearings in the axle and repack etc.
I picked it up and took it home...will see if the sound comes back.

 

I would get involved with a local toyota offroad group and see if someone can help you fix it.

 

I was wondering if the OP ever figured out his knocking problem. I just replaced rear wheel bearings and seals along with brake shoes and wheel cylinders. i now have a knocking noise when brakeing coming from the driver's side rear. i swapped drums, took brakes apart and reinstalled everything but the knocking is still present. Any ideas?

 

As I mentioned in my other posts above...the dealer originally said it was the "rear brake kit" and wanted $730 to fix it at the time. I didn't want to spend that $$ then so they were able to do some adjusting to get the noise/knocking to do away. I drove another 20K+ miles w/o ever hearing it again. When I took the 4Runner in for timing belt, water pump and brakes a few months ago they redid all the brakes. I have not heard the noise/knock again.