My car calls for 5W30 Mobil 1 synthetic oil, but I think I need a thicker oil based on a slight valve rattle. Would it harm my engine if I switch to 10w30 Mobil Oil synthetic in my car? If that is too thick, can I do a half and half of the 5W30 and 10W30? Thanks for any advice.
Jun 13, 2016 at 9:04 PM
