I'm looking for a recommendation from you guys on the OCI for my car. Car info .. '07 Focus, 2.0L with AT, current mileage 131,000. I've been using Mobil 1 5-20 (Ford's recommended weight) and a Wix filter. I've been doing 6000 mile OCI's. About 75% of my driving is in town and the rest is highway. So, the question .. is my OCI OK or would you recommend something else?