​​Over the weekend I decided to pull both diff side covers to replace leaky output shaft seals. I also replaced both side cover orings and put on some anaerobic gasket maker for preventative maintenance.

As I was reassembling the passenger side I noticed the output shaft had quite a bit of play in it. I could grab it and physically wobble it around a good 1/4". I got everything back together, took it for a drive, and immediately pulled back in my driveway because the rear end was making a pretty bad whirring noise. I assumed it was an issue stemming from the wobbly output shaft.

Got it jacked back up and pulled both rear wheels. I grabbed the driver's side axle at the diff and tried to move it up and down but it's solid. Went to the passenger side and I was able to move it up and down quite a bit. I drained the diff and pulled the passenger cover again thinking there was something I didn't get seated back in the cover. I reinstalled the cover and paid good attention to keeping the output shaft and bearing assembly lined up in the middle of the seal thinking it wasn't seated properly. Got the cover tightened back down and still the same issue. It's almost like the output shaft and bearing isn't being pushed all the way out to properly engage with the cover. With the cover off I can also grab the entire diff assembly on that side and wobble it around inside the housing. It seems to spin just fine.

Car is a 01 Z06 with 55k on the clock. Zero issues with the rear end before this. I know the output shaft was solid before I took the cover off the first time because I checked it before pulling the cover.

Any ideas? Is there something I need to align and set inside the diff to make it solid? Do I need to take the axle off the driver's side and push the output shaft a little toward the passenger side so it seats? Not even sure if that's how it works??

I read an old thread about wobbly output shafts and the issue was worn out clutch packs. I'm having a hard time believing that's my issue since I've never had an issue before and it was solid before pulling the covers. Or maybe I'm in denial that I'm going to have to pull it and replace it.

 

My opinion, the pass output shaft play within the carrier is due to worn or most likely broken disc springs...

As for the differential noise... if the carrier is not back in original spot, it will affect the pinion to ring gear clearance. The right side cover has a bearing race and shims. If the cover is not fully square or torqued down properly it will affect the clearance.


Refer to this post on the rebuilding/ torque values...
https://www.corvetteforum.com/forums...ld-how-to.html

 

Thanks for the info. After more research I'm at the same conclusion as you of needing a rebuild or finding a used diff that's in good shape.

 

If you don’t replace the bearings, you can do the carrier rebuild yourself. It’s not that hard of job. Make sure you keep track of the shims and bearing races locations and do not move them from their original location. If the differential was not making any unusual noises prior... I think you will be ok. It all depends on the condition of the existing parts (bearings and gears) are in good shape. The carrier spider gear shaft removal requires some downward pressure to remove them, a home made jig is easy to make and using a cheap hydraulic press will help in sliding out the spider gear shaft. I have done it without a jig and press... you will need to muscle it out and install it might be PIA with fresh spring discs. Good time to upgrading to C6Z components for a more robust LSD.

If I was you, I would remove differential. On a bench, set it up the differential with side cover up, reinstall the side cover and torque to spec, to make sure the carrier is seated properly. Set up a dial indicator on the ring gear and measure the back lash for baseline. If everything check out good then rebuild the carrier.

 

I rebuilt my diff with only new spring washers and it is not hard if you have a press. I have the tool to press the clutch pack down with if you need it. Lots of good write ups linked in my post about my rebuild.

 

Thanks for all the great info and links guys! I'm reading up on all of the threads to get a good idea of what to do. I have a press and a good assortment of tools so I'll probably try to tackle it. By the end of this job I'll be able to tear the back end off and drop the drivetrain with my eyes closed.

Appreciate the offer to borrow your tool! I'll PM you if I do.

 

Regarding the tool for pressing the side gear: I used 2 long sockets and some kind of horizontal bar (whatever you may find in your garage).

 

Nice