First analysis on the 350 in my 1976 K-10 Chevy truck. The 350 is not original to the truck but is a 1976 350 from some sort of GM Car with an automatic according to the block stamping. I've owned the truck for a little over three years. Had exceptionally low oil pressure when I purchased it and unknown oil from a Valvoline instant oil change judging by the filter I removed when this oil was installed. Immediately prior to this oil change I had the oil pan off to inspect rod and main bearings (all checked out ok) and I installed a Melling M-99HVS oil pump (for those not familiar this is a BBC pump made to fit a SBC that was used in Z-28 engines) in addition to the new oil pump a 28,000 GVW oil cooler was installed and plumbed with -10 AN line with a thermostatically controlled Permacool sandwich adapter. Oil pressure with the new oil pump is now excellent for an old SBC. Oil fill was 4 quarts of Mobil Delvac 1300 15w40 CJ-4 and 2 quarts of Napa All Fleet 15w40 CI-4+, top off oil was .5-.75 quart of Valvoline SAE 30 I had laying around and open. Silicon in the UOA is probably a combination of sealant used on the 4 corners of the oil pan gasket and the new silicon rubber Fel-Pro one piece oil pan gasket and to a lesser extent from silicon sealant used on the valve cover gaskets that were replaced immediately prior to my ownership. High copper is likely due to the new 28,000 GVW copper oil cooler. Filter for this oil change was an AC Delco PF-1218 posted in the filter section. New oil in was 6 Quarts of Napa All Fleet 15w40 CI-4+ and a new Delco filter.
Enjoy!
Enjoy!