Ok, ill start the story after I replaced my 2nd broken diff. I bought a used OEM diff, installed it, then about a year later I got these odd clicks at very slow speeds. Louder and more prevalent in reverse.

I used a video camera to determine that the clicks occur 4.1 times for every 1 revolution of the wheel. Replaced the diff. Then 1 year later again, same problem. Decided to drive on it for a while anyways. Cause I only really noticed the 4.1 clicks at slow speeds. Then all the sudden, after traveling on the freeway at 70+ the noise becomes a grindy, marbly, chattery sound that occurs when I am trying to hold a specific speed over 60 mph, in addition to the slower speed 4.1 clicks.

(whenever I mention 4.1 clicks, I

 

https://www.s2ki.com/forums/index.php?showtopic=529975 ...you should try and open up the diff to see if you have a similar situation. Could it just be the way you drive? High launches? etc...

 

I have drained all my diffs. Never had any chunks. I do drive my car extreamly hard. And spend alot of time on the track drifting. However, since my last 2 diff installs, I have driven very carefully. And the problem still returns. Almost as if something else is breaking the diff at high speeds or its not even the diff, but the prop shaft, or alot less likely the transmission. I wont pretend to know, cause I seem to guess wrong every time.

 

Are you sure it isn't your wheel bearing?

 

I've had wheel bearing problems before. I know its not that. Judging by the sound it has to be coming from the differential area. And judging from the ratio of clicks it should be coming from in front of the pinion. (or at least the one noise should be in front of the pinion) There is a slight chance that its coming from the transmission area. In all likelyhood I believe the problems must be related to one of these items based on the clicking ratio...

 

Have you taken apart one of the diffs to see if you could determine exactly what is failing? Do the diffs make the noise when they're out of the car and you turn them by hand?

 

You guys are missing it. It's the propeller shaft (drive shaft). It's the INPUT of the diff that has the ratio of 4.1 to the wheels.

I'm betting the rear CV joint in the drive shaft is bad - probably dried out the grease and it's worn really bad. The noise will come and go with speed, load (acceleration), and heat. Heat meaning how long the car has been driven continuously or at what speeds.

edit - Mine was clicking like mad for a week, then went away for over 6 months. It came back slowly and gradually got worse. Here's an audio clip of the clicking at several different speeds and conditions (180k mp3). Bear in mind the car has a SC so the "whirring" noise is normal, just listen for the clicks - it will be obvious.




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[QUOTE=modifry,Oct 10 2007, 02:04 PM] You guys are missing it.

 

Yeah, all the diffs with the problems I've mentioned, I have taken apart and can not see any signs of damage. Nor can I hear anything turning by hand. It just seems logical that it must be the prop shaft. But if so, why did changing the differential fix the noise for a whole year? A year of rough track time. I'll be replacing the prop shaft tomorrow (when the part gets here). My suspicions are it may fix it, but the damage may already have been done to the differential (if it has anything to do with the diff that is).

 

Bump for photos and audio clip added to my previous post.