Hi everyone.....I'm a newbie to the forums here and to the website in general. I have a question about the compatibility of synthetic motor oil and the Bosch Premium oil filters. I have a '99 Avalon that I just love, and I've been running Mobil 1 oil in it since I bought it 2 years ago. So, yesterday I picked up a jug of M 1 and a Bosch Premium filter, got them home and noticed that full synthetic oil was only listed as being compatible with the upper "tiers" of the Bosch filters, not the basic premium filter. Any ideas as to why this would be ? Is there any harm in running the full synthetic M 1 with the filter that I have purchased ? Thanks for any input you might have on this.