I think your rig has the 9th injector, right? I know on the LMM's they didn't recommend extended drain intervals because of oil dilution from basically washing the 8th cylinder and fuel leaking past the rings on the exhaust stroke. Are you sending your oil out for analysis to get these findings? Just looking at the oil will tell you exactly one thing: color. If you want to to know about fuel in the oil, or viscosity breakdown you better have a lab check it out. I have a lbz with 6k miles on my oil my amsoil 15w-40 hd marine 12tbn oil. It has a long name but I think thats right. it has warmed up here. Oil pressure at startup is about 80psi. I leave my truck plugged in unless I'm driving it. If I start it in the morning after being plugged in all night it will kick into high idle. If I let it run for 5 min and then take off the oil will not be higher than 80 psi during driving. Once it is warm it sits around 40-50psi under load and 25-30 at idle.
2009 GMC CCSB LMM ~ 4"MBRP Deleted/S&B ~ CTS2 ~ DSP5 from Rob ~ CAT ~ Leveled w/ Kryptonite UCA & 5100's
2006 CCSB LBZ ~ 4" exhaust/AFE intake ~ Pyro/Boost on the a-pillar ~ EFI Live w/ dsp 5 ~ CAT fuel filter ~ 5100's
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