ok so i got my car back today they said it was because of me switching to synthetic too soon. But the part that pisses me off is that they did a synthetic oil change and a rotation about 70 dollars of service and then told me to get a regular oil change done untill 15,000 miles(I'm at 14000 now) They wanted to charge me for the regular oil change 40 dollars and all of the other service. does any of this make any sense to any one. I decided to just buy some more synthetic oil and add untill 15,000 where the guy said it should be fine.