@cavell gave good advice concerning oil flow when the engine is warmed up. The other issue is start-up. When the engine starts, the 5W30 will lubricate better than the 10W30 will. Since most wear occurs at start-up, using 10W30 (or 10W40) will increase engine wear compared to 5W30. Do you have excessive engine wear or is this just to prevent wear in the future? If you don’t have an oil pressure problem now, just keep using the 5W30.
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