Run 10w-30 in the summer months and 5w-30 in the winter months. If in canada 5w-30 year round is recommended. I run 10w-30 all year round because I only change it slightly more than once a year lol. I'm running mobil 1 but any name brand oil is fine with me. Remember if you have any other oil leaks synthetic will only leak more. I had that issue when switching to synthetic but I just fixed the things that were leaking.