speedf50

So my s2000 has 189k and it's clear that the previous owners were not kind to the car...

Pretty much since I got it I've noticed a clicking from the diff/rear end in tight low speed turns and u-turns. Below is a video that pretty clearly shows the noise:


From what I've read and after replacing the axles with lower mile ones (I also had the axle noise and vibration under accel but that is gone) I'm pretty sure it's my diff. I also replaced the diff mounts with poly ones and re-torqued everything down.

I decided to track the car with the current diff as I have a spare waiting to go in, but it held up fine at buttonwillow, I even won the J's racing street class time attack!

I'm most likely going to run this one till it completely gives up, but am curious as to why it makes all this noise and still works ok? Is it just a lucky diff? Maybe something else? I flushed the fluid and replaced it with amsoil 75w110 which might be helping it last, but the drain plug was covered in a scary amount of shavings!

Thanks for any input!

SpitfireS

Lift the rear, put it in gear, turn one wheel (engine off, no handbrake...)
How does it feel?
Does the other wheel turn the opposite way?
Do you feel anything while driving through turns, especially u-turns?
If you get on the throttle a little, mid corner-corner exit, does the front want to "oversteer"?
Maybe the side washers in the Torsen unit are not in the best shape anymore.
Small shavings & powder on the magnetic drain is normal, no bigger parts in the oil you drained?
(did you check?)
Try 75W-140.
As long as the final drive is ok the diff will not BOOM easily.
AFAIK most-if-not-all diff failures are final drive failures.

Slowcrash_101

That small noise when doing tight turns in a parking lot are no biggie IMO.

Merknsissys

I also have this sound and I was told that the carrier is likely cracked and the chatter is from the diff trying to spit but again I was also told that until those metal shavings eat up the FD ill be fine :/ still seems like a time bomb...

S2KPUDDYDAD

It is the LSD, it is damaged. The sound is the planetary gears binding when little to no load/demand on them. You may find if you leave the car in gear as you make your low speed turns that the sound goes away. Once load/demand is put on the LSD it will be forced past the binding.

The planetary gears are tweaked or cracked inside the LSD and do not mesh correctly anymore, this is causing the binding. The most common reason for this to happen and cause the damage is wheel hopping the car.

Merknsissys

So just curious, am I correct on the ticking time bomb? What happens when the diff cant push past the binding? Has anyone experienced exploding tail sections of ap1 transmissions when the diff fails or is it the weaker link of the two?

S2KPUDDYDAD

Best to replace the LSD if you start dragging the inside wheel like if you had a spool diff. Change the diff oil every other engine oil change and inspect the drain magnet for metal bits getting worse over time.