Replacing differential bearings - Questions

[Rrjr24]

Hello everyone, hoping someone can help with some questions...

I'm attempting to change the differential carrier bearings on my 2002 Boxster S manual tranny after narrowing a whining sound together with a knocking sound when getting on and off throttle - we're pretty sure it's coming from the differential. We've ruled out other possibilities like axle CV joints, wheel bearings, etc. My local Porsche specialist also checked the car and agreed it was coming from the diff - most probably worn carrier bearings.

We've removed the differential and upon inspection I have a few questions:
1. I don't see any shims installed on either side of the differential. Is this normal? I thought there were always shims used to adjust backlash, etc. Would I only see them if I remove the bearings??
2. There are some engravings on the ring gear.,..anyone know what those refer to?

Thanks in advance for any info!!

[JFP in PA]

Item #10



The backlash or free play should be in the range 0.12 to 0.22 mm. Here's a picture showing its measurement with factory tools.