Sorry for the off topic post, but the Toyota and Lexus newsgroups are
dead. Since there are plenty of knowledgeable and opinionated people
here I am throwing this out for your comments.

Five months ago I bought a certified 2013 Lexus RX350 with 16K miles
from the dealer. The first service call is complimentary and that
includes an oil change. My dashboard service light came on around 5K
miles so I called the dealer to schedule the oil change. They told me
this vehicle uses synthetic motor oil and recommended oil change
intervals are 10K miles. I looked in the service manual and sure
enough that's true.

http://www.lexus.com/pdf/service/RX_WSG.pdf

In my Toyotas I would change the oil at 5K miles using conventional
oil. It makes me somewhat nervous to go 10K miles between changes but
I guess synthetic is that much better and doesn't get dirty or break
down. I've reached the 10K mile point and am going in today for the
service.

The next oil change will be done by myself. Does anyone else use
synthetic motor oil and how long do you go between changing it? What
brand do you use?