I started a new job 2 months ago (commute into NYC via bus) and rarely drive my 05 Forester during the week. I estimate that I will go from annual mileage of 16-18k a year to 8-10k a year. I have been using Havoline 5-30 and subaru OEM filters at 4k intervals. on average, I now use the cae 2-3 times a week and not everyday. Given the above, should I reconsider anything or just stick with the same schedule.