Knocking Sound When Tire Stops Moving? Help Diagnosing

Hi. I have a 2005 Camry LE, about 180k miles on it. Engine is 2AZ-FE. Automatic Transmission is U250E

I’ve started noticing that when I brake at low speeds, right before coming to a stop, I hear a knocking sound. I only hear this sound in this situation only. I hear this coming from the front area of the car.

I looked online and it seems this is a symptom of a bad brake job, of not tightening the bolts all the way. The last time I did a brake job I made sure to torque down all the bolts to the service manual.

I lifted the car up and rotated the tire, and was able to replicate the noise. I hear it when rotating it and then switching to rotating it in the other direction. It’s a knocking sound.

I take the tire off and rotate the wheel hub and still hear the knocking sound.

Does anyone know how I can further troubleshoot and diagnosis the knocking sound?

Thanks for any help.

Looking online I think it might be a bad CV axel? But I’m not sure how to confirm this, and which side is the problem.

Can you post a sound clip?

Let me know. Thanks again.
You may have to turn your volume up a little to hear the sound.

I tried the wiggle test for ball joint play and it was fine, on both sides. Meaning I put a hand at 12 o’clock and 6 o’clock and tried to wiggle the tire, and then again at 3 o’clock and 9 o’clock, there wasn’t excessive play.

Perhaps the brake pads have some wiggle room in the calipers.
Aftermarket pads?
Are all the anti-rattle clips in place?
Turn it with the wheel off and watch for pads shifting.

If it is just pads shifting slightly I’d leave it be.

1 Like

Did you recheck the torque on the caliper bolts?

Some cars have caliper guide pins with anti-rattle feature.
So, you have guide pins and caliper bracket mounting bolts. 2 different bolts .
You have noisy/loose brake pads?
With wheel off, the rotor can make noise due to clearance holes in rotor for lugs. if you try and rotate wheels. Sometimes. Some rotors have small hold down screws.
How are you turning rotor with wheel off? What are you applying force against?

Hey thanks. I’m sure I torqued it down to specification and double checked. But it’s certainly possible I forgot one. However I do recall that when I applied grease to the guide pins this little black piece (circled in yellow) came off inside of the caliper. I couldn’t get it out and just reinserted the guide pin. I don’t think this is the cause of my issue though? I’m also wondering what exactly is this black piece called, and what function does it have?

So with the tire off I was rotating the wheel hub by handling the threaded rods for the lug nuts by hand, with all the brake hardware and rotors in place.

I’m using non OEM brake pads and rotors.

Sounds like one way I can rule out a brake hardware issue is by removing the caliper and rotor, and try rotating the wheel hub by hand this way, to see if I still get this issue.

I put on new disc rotors on both sides about 6,000 miles ago. I was getting bad squeaking, so I re-applied grease to the back of the pads and guide pins around this time, I didn’t do that when I originally did the brake job. I’m also sure I have plenty meat on the pads left too.

I’m just now having this knocking issue though. Although I should mention I did hear some knocking sounds before. But it was very rarely and only while traveling at slow speeds (doesn’t seem to be happening now and I’m experiencing a different issue). So I just ignored sense it very rarely happened like maybe for a few minutes every couple of thousand miles. I don’t know if it’s related or not.

[quote=“YoshiMoshi3, post:7, topic:182324”]
However I do recall that when I applied grease to the guide pins this little black piece (circled in yellow) came off inside of the caliper. I couldn’t get it out and just reinserted the guide pin. I don’t think this is the cause of my issue though?
Just to recap, you botched the job and now wonder why there is a problem. Hmmmm. Seems to me you need to start over and do it right.

1 Like

I would call it a collar, or insert.
It takes up all the slack between pin and bore, but without dragging metal-to-metal.

Consider replacing the pins, they’re not expensive.

1 Like

Rotors could be warped already if they’re cheap aftermarket. The sound could be the pads shifting, clicking against the caliper as the pads ride over a certain part of the warped disk. You should be able to see the pads shift slightly in the caliper as you rotate the wheel if this is the case.

If all else fails, I’d go back and inspect my work. I’d also fish that rubber isolator that came off the caliper pin out of the hole it’s in and possibly replace the pins. I probably wouldn’t replace them if they aren’t rusted too bad and if I could reattach the rubber. Or just buy the one (or set) that needs replaced. Make sure all of the anti rattle clips, springs, etc are in place. Look up the oem brake hardware on a Toyota parts site. Make sure it’s all there.

Anti rattle pin could be in top position or bottom. Assuming prior mechanic installed it correctly.

Well I got some good news, kind of. I don’t think it’s brake related! I was able to replicate the noise without the brake calipers and rotors on.

I got the front of the car off the ground. Both front wheels up. I removed both wheels, both brake calipers and both rotors. I then grabbed ahold of the studs of the wheel hub and attempted to rotate the wheel hub.

The right hand side, I hear little to no knocking, I think it’s just me hearing the sound from the other side of the car. Here’s a video of the clip of the right hand side. You may have to turn volume up.

The left hand side however, I hear the knocking sound. See the video below. You may have to turn the volume up.

I inspected both CV axel boots. All of the boots seem to be undamaged, I don’t see signs of leaking grease. The CV axels are very rusty, but I don’t think it’s an issue. Both of them are the original OEM ones from 2005 and I have over 180,000 miles on them.

How should I trouble shoot this further? Is this a problem worth fixing? I guess it’s kind of hard to say without knowing for sure what’s making the sound.

I guess if it’s not a sure sign of something in particular being broken, I could take the wheel hub off on the left hand side and try just rotating the axel without the wheel hub attached. This would narrow it down it down from not being a wheel bearing issue. Although I thought wheel bearings, when the fail, it’s more of a whining sound, and not this knocking sound I’m hearing.

I suppose something could also be wrong with my transmission.

Thanks for any help!

May just be slack in the driveline. I don’t think I’d worry about it if there aren’t any other issues. Wheel bearings would be a different sound. I believe I’d let it ride.

The ‘right side’ video doesn’t show you changing the direction of rotation, did you do that?

If this sound is new then I think it is driveline slop.
Cv axles? Differential and/or bearings?
Live with it?

I would not worry about it right now it is very slight drive line play. you have 180k on your vehicle. you might be on the next one before it gets worse to worry about it. if it does get louder then I would check it out further. for right now… turn up the radio.

Thanks guys.

So when I refer to the “right side” I’m referring to the driver side of the car, furthest from the transmission. The “left side” is the passenger side, closest to the transmission.

For the driver side, no I did not try and rotate it the other way. I can’t believe I forgot to do that, and that’s a good point.

Sense every one says not to worry about it, I probably won’t.
I would like to understand though what may be causing the issue. Just put it on the list of “thing to eventually do”.

Would this be a CV axel problem or a transmission problem? Or there’s not enough to know what may be the issue? My transmission is U250-E which is an automatic transmission. It is a forward drive car.

just so you know for when you order parts… the passenger side is considered the right side and the driver’s side is the left. just like when you sit behind the steering wheel. unless you have a right-hand drive vehicle

The OP said it is right hand drive.

sorry I missed that.

1 Like