Did a quick search and it didn't give clear answers.

I have a base 07 6MT open diff 350z. Looking at getting a separate pumpkin to build a LSD differential from an AT 03 350z. From what I gather, the housing from 03-08 are the same. Meaning I could buy the pumpkin then piece together the kit with no issues correct? I understand the Auto came with 3.3 gear and different size stubs. I would most likely end up getting a 3.9 FD. Is there actual different ring and pinions based on Auto vs Manuals? I also understand that the Autos had a thicker ring gear. So if I wanted to reuse the stubs (unequal length) would I have to get a Quaife diff that is designed for automatics? Any clarification would be appreciated!

 

You'll also have to change out the input flange. Manuals have a 4 bolt flange while the ATs are 3. Did you want 3.3 for FI purposes? If staying NA get a 370z or G37 6mt rear diff for the 3.69 final drive.

 

The auto differential input flange on the 350Z and G35 are all 4 bolt from what I have seen. The three bolt flanges are from the Auto G37s only.

 

Hi Tom,
I assume you are the one who bought my old diff on eBay. If you have any more questions, contact me in a PM and I'll send you my personal email address. I sent you a contact request on LinkedIn too. I'm interested in hearing how your project turns out. As for your original question, the ring gear in the A/T is not thicker, it's the pinion that is 20mm larger in diameter to accommodate the extra tooth. On an aside, I got an email the other day from Quaife, they now have a new $1M dollar gear cutting machine from Liebherr. You can Google for it, it's pretty cool. I assume they are looking for contract jobs to pay for it now