I love my '09 Vibe with the 5 speed stick and. . .the 2AZ-FE oil burner under the hood. I had two vintage oil burners before (an '81 and an '82 123 series Mercedes-Benz 240D). Different kinda oil burners, though
Okay, so we Pontiac owners are out of luck with getting Toyota to evaluate our engines, let alone replace them. Okay, I can live with monitoring my oil, but I am curious about the possible benefit (or harm) of using heavier oil than the specified 5W-20. I have had a mechanic recommend using heavier oil, and I have read that heaver than specified oil may not coat the engine parts sufficiently, because modern engines have been engineered with such close tolerances. I have sorta split the difference: I let a GM dealership change the oil and use the specified stuff, and I add 5W-30 as I lose oil between changes.
Any opinions on whether heavier is good, bad, or indifferent for this engine?