well. hit up the dealership today. $8.65 later I had a new o-ring. came home and pulled the pan and sure enough. torn up o-ring. popped the new one on. bolted everything back up. dumped in some oril. psi shot right up to 50. drove around for 30 minutes and its running great.
huge thanks to everyones input and links to save me from spending a lot more money.
now onto the next issue. the ls4 oil pan I bought off ebay is leaking. right in the middle of the pan. it must have a hair line crack or something. I can wipe the pan clean. then I slowly watch it bleed thru. its kinda creepy.
bad o ring.