Here's another good thread with all the pans and part numbers:
http://www.ls1tech.com/forums/conver...x-oil-pans.htm
Cadillac CTSv :
Capacity: 5.5 qts
Oil pan: 12577901
Oil pump pickup: 12577906
Windage tray: 12558268 (same as Truck "C/K)
Dipstick tube: ?
Dipstick: ?
O-ring for Oil pump pickup:?
Oil pan baffle: 12577904
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