I usually run 5W30 non - extended performance 5W30 synthetic oils (Valvoline Advanced , Quaker State Full Synthetic, etc. ) in my '17 Sonata GDI 2.4L non - turbo engine along with a Fram Ultra oil filter. My OCI's accordingly have been 4K ~ 5K miles / 6 months max . In the same vehicle I thought I would try the M1 5W30 D1 / Gen 3 EP synthetic oil for 7.5K miles / 12 months (whichever comes first) and see how well the GDI engine plus the M1 5W30 EP play together? *Although the M1 5W30 EP oil + Fram oil filter are rated up to 20K miles , I would never attempt such mileage in a Hyundai GDI engine due to soot and possible fuel dilution this engine produces . With 7.5K miles / 12 months as the new test OCI in the aforementioned Sonata with the M1 EP oil I will get a UOA to be sure , but the 7.5K mile / 12-month OCI using M1 EP oil should be a safe OCI in mixed, typical driving conditions ... Your thoughts and experiences ?