· Premium Member
If I'm not mistaken, synthetic oil is a requirement in the CT and not an option. Service intervals are 5K in the CT, but as jonacrombie mentioned, the oil is changed every 10K. The 5k intervals in between are just "check ups" I believe, may even include rotating the tires. The CT can go the 10K miles vs. the 5K miles in the IS because the gasoline engine isn't running the whole time and when it is, it's running with less load at times due to the battery assist.Does Lexus up the service interval from 5,000 to 10,000 miles if you use synthetic oil ?