I last posted about the expense of the 15,000 mile service. They didn't have time to do the whole service at one time, so they changed the oil and the service called for changing the air filter ($56.00). I have a high flow A/C ordered and figured it would be coming in before long so I thought I would save myself a couple of bucks by letting it go. After being set off and delayed by the delivery date I decided to check the filter. It was an absolute mess. It had water in it (I have been in several southern rain storms in the past few weeks), it had oil in it and the bottom quarter was as hard as plastic with visible gaps in it. It should have been changed several hundreds, if not thousands, of miles before. So, my advice would be to probably check it at least every 5,000 miles when you change oil. Don't wait for 15K...