Thanks for the explanation, PTguy. You must have some background in oil analysis, or you must also be a member on BITOG.The viscosity is out of spec. The viscosity at 100C for 30 wt should be 9.3 to 12.49 centistokes. Your test showed 8.4 cst. Your Pennz started at 10.3 according to their data sheet. That loss could be from shearing, or it could be from gasoline dilution. Do let us know when the lab responds to your question. The silicon at 21 ppm could be either silane anti-foam additive in the oil or dust that passed through the air filter. The wear metals are nice & low. Shell (Pennz) uses moly in the oil for anti-wear. Castrol uses a titanium compound to do the same job. You'll see the difference if you get an analysis with Castrol. The zinc phosphate compound in the oil is anti-oxidant and anti-wear but leaves a high friction layer on the metal. The addition of either the Molybdenum dialkyldithiocarbamate or (cheaper) similar oil-soluble titanium compound provides a low friction hard antiwear layer.
Other way round.The kinematic viscosity test, measured in centiStokes, is by pouring a specified volume of oil, at the specified temperature, through a specific orifice and timing it. The thinner the oil, the faster it flows.Does lower cSt = more viscous?
If the previous oil change was made by a Mazda dealer, overfill is a norm.No, I checked at different temperatures. Once after the engine had been driven, then parked at home to check about 15 minutes later. The other time was cold engine in the morning. Both times the engine oil was above max line.