I think we need to read a service manual; maybe it is switchable between miles and days - my '04 definitely reads miles and it doesn't even change at less than 100 (ie; it counts down until service mileage and then counts negative numbers up if it isn't reset. I think i'm getting the max miles out of oil changes - it's only requested three in 28k and my icon hasn't come on yet after the last one. I've found a german car specialty shop that likes the car and only charges 59 bucks for the change. It's called "Auburn Foreign Car", It almost seems like they get bored working on all the benz's, porsches, and bimmers and like the change of pace !