I recently got back my used oil analysis from Blackstone Labs from my initial use of the now discontinued AMSOIL Series 2000 0w30 in my 06 CTS-V. The Series 2000 0w30 was replaced by the AMSOIL Signature Series Synthetic 0w30 (http://www.c66racing-synthetics.com/Product%20Bulletins/SSOPB.htm) which I plan to switch to on my next oil change.

For those interested in seeing how the AMSOIL performed as compared to my previous analysis using the factory fill Mobil 1 5w30, here is the data:
Cadillac CTS-V Used Oil Analysis – Mobil 1 5w30 vs AMSOIL 0w30 (http://www.c66racing-synthetics.com/TestResults/CTS-V%20AMSOIL%20UOA.htm)
:cheers: