I like the thicker oil and shorter oci due to soot, fuel dilution, etc. but I don't think a little thicker oil can prevent the bearing failure. It's an engine issue that Hyundai is covering with unlimited mileage and it's nice of them but I doubt if oil can resolve the issues before the fix! even if you use 40 grade and oci of 3000 miles, it could be just matter of time.
I've read reports of engines running fine using 5W-20 with over 100K miles and some failing at 40K, 60K and 80K miles with all sorts of different OCI and viscosity grades.
Maybe Hyundai got wiser and decided to ditch the 20 grade CAFE oil. Having said that, Toyota recommends 0W-20 for my Tundra with 10K oci ... so the 20 can't be that bad after all. Granted it's a MPFI and not GDI and easier on oil.
I've read reports of engines running fine using 5W-20 with over 100K miles and some failing at 40K, 60K and 80K miles with all sorts of different OCI and viscosity grades.
Maybe Hyundai got wiser and decided to ditch the 20 grade CAFE oil. Having said that, Toyota recommends 0W-20 for my Tundra with 10K oci ... so the 20 can't be that bad after all. Granted it's a MPFI and not GDI and easier on oil.
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