My friend is really delinquent when it comes to oil changes. He often goes 7000 or more miles on dino oil. I convinced him last December to switch to synthetic, so he could have a measure of extra protection when he forgets to change the oil. He now wants to do extra long OCIs, in the range of once a year. I've explained to him that a UOA would be the best way to determine the proper OCI, but he's not interested. Which would be the better "once a year oil" for his 1998 Honda CRV , German Castrol or Amsoil 5w30 ASL? The engine burns/drips about a litre every 4000 miles, so it would require about 3-4 litres of top up oil over the course of a year.