Now maybe someone will understand why I put 15W50 Synthetic in every engine here; unless , the engine is a winter engine.
Well I don't understand the need for a light 15 grade oil that acts like a 50 when at 212F. Especially when Briggs and all other engine manufacturers state, using multi-grade oils will cause more oil consumption. You can use aviation grade oil, doesn't impress me a bit.
No sense using NASA grade oils in mower engines. A Briggs will run on stale crackers and water LOL. Plain ol' SAE30 has been around since dirt. Zero, I repeat zero documented oil related mower engine failures and going strong.
slomo