Ratcheting clank from front left at 8-13 mph slow regen and slight turn right

Greetings all,
My 2007 with 58k on it started making the sound of a 'ratchet clankety clank' about at 56k while lightly braking with regen around 8-13 mph (slow and quiet enough to hear it best) and while turning slightly or more to the right. If I'm on a hill and can maintain the conditions, the sound will continue.

I've spent many a night searching here and elsewhere, learned a lot about strut and cv noises etc. At 57k I took it to a dealer who has a very nice service dept and they rode with me, agreed that they heard it, checked out the cv by hand (my first suspicion) and said all felt fine, that it was recorded at least (my concern being near 60k, std warranty).

My fear is something in the transaxle- I can replace almost anything else being a car guy but I know the tranny is expensive. Last time I had the wheel off all was ok. Replaced the tranny fluid at 53k and looked very clean, fill amt was good and is not leaking.

I've attached 2 quicktime movies for opinion, and would appreciate some considerate guesses. 60k miles is coming soon.

Best regards.

 

FWIW, I have not yet checked the LF wheel bearing for play, but that could be a suspect, though bad bearings do not click in my experience.

 

The WS. Was of course darker than new WS fluid but not very much darker at all- surprised me really. Drain plug had hardly any filings at all.

After work today I will pull the wheel again and inspect the brake. If it were the brakes, I'd expect some noise at other speeds and once regen turns off, but IT ONLY OCCURS WITH REGEN ON (so above 7 mph).

Thanks!

 

FOLLOW UP: I can make this noise now every time, while slightly turned to the right or the left, while regenerating at slow speeds >7mph (slower makes the clank go slower, stop regen braking and the noise stops (transmission must be loaded)). After spending much time looking at the CV joints and the wheel bearings, I have narrowed down the sound-- it is in the Transaxle

I'm 99% sure its the spider gears going bad in the differential. I now have 63k miles, no extended warranty. I have only driven in winter weather once and did not have traction problems, so no abusive spinning etc. even though traction control prevents this. I'm at the dealer now, will follow up. Hoping for the best since I originally brought it to them w/ same sound at 56k, and since I posted here and have videos from 58k.

 

Well, dealer techs couldnt replicate (didnt know what to listen for etc) but then I drove and did it every time. Techs think its the brakes (but-- if it were brakes, it would do it going straight too I'd think, not just turning). Agreed to pay for a brake job (would normally do this myself), and if brake job doesnt solve the noise, the cost will be $0.

 

Update: It wasn't the brakes (free brake job...). Picked car up tonight to drive for now-- was told it will be a couple of days as the dealer techs want to speak with toyota corp techs on the issue. Was also told it shouldn't be a prob covering transaxle under warranty since original issue was brought up and brought into dealer before 60k

May reveal the dealer when this is finished

 

Update:
Toyota corp techs recommended changing the wheel bearings. The dealer changed the front left (closest to the noise), was able to have it covered under warranty! . No fix though . Took care of the inverter coolant pump recall while it was in. Still pretty sure its the transaxle differential, which isnt getting any quieter!

From the best vid attached in original post, extracted audio, band-pass filtered with spline curves and amplified. New mp3 attached (is during slow regen while slightly turning right). Noise is obvious.

Stay tuned for what Toyota corp techs plan next.

 

FINAL UPDATE, hopefully:

Toyota technical required replacement of the left front CV axle next. This turned out to be the culprit, and was an original suspicion. This is a strange failure because there was no clicking when turning any amount other than just ever so slightly, and only when regenerating. This means that the outer CV was fine but the inner CV joint (at the transaxle, the one that has the slip joint in-out as suspension flexes) was failing. Unless a CV boot fails (mine was fine), this is usually the rarer end of the CV to fail. (Except maybe in some independent front suspension 4x4s with front suspension lifts).

FYI, hope this helps someone.

 

UPDATE: As mentioned before, as this sound became louder and more repeatable, it became possible to replicate it while slightly turning left as well, same speed and regen conditions. As it turned out tonight, I was going down a steep neighborhood hill to visit family, replicating conditions, but slight turn left instead (turning left I didnt check very much since the last dealer fix). I HEARD THE SOUND AGAIN. While on the hill, I turned slightly right and could not replicate it anymore, as were my results after the fix (sound was always much louder when turning right). My guess is the right front CV inner joint has the same problem. It seems that the direction has to do with the source of the noise (side of bad CV possibly). Honestly here, I'm at 64k miles, and take great care of my vehicles. This almost seems like a mfg problem here- undergreasing or poor quality control on the inner joint. Guess I have a call to make Monday morning...
I will say this- if Toyota brand CVs are only good for 60k miles, then there's no reason to pay $500 for one vs. a cheap reman option at an autoparts store.

 

Thanks, this is def turning / not turning w same suspension position, but I will check it out