How much metal parts is too much in differential oil ?
 

Hey, I've had a weird sound for more than 1 week and I don,t drive a lot my miata since that.

I decided to check the oil in my Torsen differential to check for metal parts because after reading on the forum, I found out that the sound could come from the pinion bearing ( anyone can confirm that ? ) And with a bad pinion bearing, the gear would use incorrectly.

Video of the sound :
I changed my differential oil 6 months ago. When I changed it today, the oil was darker, with a little bit of metal residue on the magnet.
So my question, how much metal parts / residue is too much ?

Keep in mind I changed the oil only 6 months ago. Here is some of the metal parts I found.

My car is stock and I did maybe 60 minutes of track day

https://www.miataturbo.net/attachmen...ine=1380237374

https://www.miataturbo.net/attachmen...ine=1380237374




Also, maybe someone will be able to answer me about this, I sprayed WD40 on the UJOINT and differential flange and the sound was less present. Is it possible for the WD40 to go to the pinion bearing and lubricate it ?

CHECK YOUR BRAKES

Also, what country do you call home?

Pfffttt

I've taken teeth from what i think is off one of my spider gears out of my differential. It's working fine currently.

That looks like nothing to me.
The squeak sound sounds like something external. Not inside some type of gear casing.

Yes I checked them, they are all good...

I'm from Quebec city, canada

And the pinion bearing would be an inside or outside sound ?

If i recall, that bearing is the last thing to be installed so it would be inside. I think.

Noise on accel and or decel?

Only on decel !

almost sounds like an axle or driveshaft rubbing on something.

You wouldnt get squeaks from a fucked diff. You say you checked brakes. I take it by that you mean theres tons of material left on the pads? Does the sound go away when u pull the hand brake? Perhaps the half shafts are rubbing on something? Do a tight max steering angle turn left and right see if the sound changes.

Also dont spray WD40... dont spray that shit to "lubricate" crap.. its not a lubricant.. its a water displacement spray. Get a real lubricant and spray it on there.

it's your brake shields.

Oooh, nice, the brake shield.

As stated before.

CHECK YOUR BRAKES! I'm talking about all four wheels off the car, pads off, calipers off, brackets off, check all bolts for the shield, and then go from there. Lubricate sliders properly and I'll bet you'll find the squeak.

God damn it, I wish you were closer to me so I can show you the sound in person. I bet you would change your mind !

The sound only appers when the clutch is engage on deceleration. If I push the clutch pedal, the sound dissapear 100% .

I took it to a mecanic and he told me It was something about the drive shaft because it's only making the sound when there is no force pushing the driveshaft (translation from french to english haha)

But yes, I'll recheck all the bolts form my brake and the pads. ;)

Make sure your alignment of the ppf from diff to transmission is within spec. I don't think i've heard of it causing the exact sound you state, but it does cause other annoying noises so its worth it to check.

So I checked all the brakes, I changed the pads. The sound is coming from the driveshaft / differential .

I've put lubrification on all the ujoint and the sound is still 100% here.
I'm really thinking it's the pinion bearing from the differential (torsen) ... I heard small clicking last day when I was accelerating hard -__-

Try putting the car up on jack stands, removing wheels, and put into gear, then can do a walk around.

Just don't wear loosing fitting clothing when getting near spinning parts or you will be fucked

if noise is not there its something with the front wheels

Then you disconnect the driveshaft and pull it out of the trasmission and narrow it down ever further.

sound is coming from rear 100% sure. I did put the car on jack stands and I went under with the car engaged in reverse.

The sound is coming from the driveshaft / differentiel