Using 5W-40 on Z's with no oil cooler

FL 4Motion

With an appropriate oil cooler, aka 19 row, for your (OP’s) use case, the type of oil is almost irrelevant as long as it’s the manufacturer spec, ie 5w30 in this case and it meets manufacturer specific requirements (ex. Audi/VW spec, or Porsche spec etc).

For “normal” use, which is what op is doing, regular oil changes every 5k miles or 6 months and I can almost guarantee the engine will go at least 200k miles with regular maintenance.

This isn’t some exotic high strung power plant or a turbo engine, it’s a vq.

Don’t sweat it.