I would run the Synthetic oil that you just put in for about 3500 miles then I would change the oil about 7500 miles if you are using a good filter, please say you are not using fram? Mobil 1, K&N, or Amsoil filters are the way to go. There is one more filter that is really good too but I can't remember the name of it off the top of my head. Try googling oil filter tests, etc and see what you come up with. Good luck.
P.S also I would run some fuel injector cleaner too, be careful though and mix it correctly or you could damage your fuel injectors. The best thing to do is search and read as much as you can so that when you go to the store you will know exactly what you are looking for.
