Mine did the same thing. It smoked out of my vented catch can & I found coolant in the oil. I tore the motor apart and among other things it was blown out rings & a cracked cylinder wall. I know that doesn't make you feel any better. Best of luck to ya!!
2009.1 PBM Pontiac G8 GT
Dream bumper; HPTuner Pro 2.23; LM-1 WB; Livernois Stage 1 cam; GMPP P&P LS3 heads; Ported TB & LS3 intake; BC Racing Coilovers; MS Camaro 20's; 4 wheel Brembos w/ D/S rotors; DT LTs; HSW wet kit-125 shot; Magnaflow AB's; X pipe w/ res delete; Rotofab w/HSRK; SLP UDP; Camaro 3.27 diff; BMR bushings; BMR Toe Rods Trailing arms & F/R Sway Bars; DIY Black trim & handles; Black LED tails