Just changed my wifes oil in her 2 month old Kia Rio. I am planning to change it every 3 months regardless of low KMs. The car has 1288 km on it and as I was changing oil I noticed it smelt really gassy and looked greenish. She does small trips on city like maybe 10 km a day I am wondering between the short trips and the engine breaking in would it make the oil like that?? Should I just change it every 3 months regardless? Any suggestions on a reasonable oil for the Kia Rio 5 2008 ?