My step daughter is 15 1/2 years old. She at the point that she no longer wants to visit her dad since he is 2.5 hour drive each way and because of all the school and weekend activities here in San Diego. We have been flexible enough to make the around trip almost very weekend. He picks her up on Friday and we pick her up on Sunday. Additionally when he moved out of San Diego County and he did not notify us in writing nor did he request permission from the courts. It's my understanding that when one parent moves more thatn 36 miles from the chlids custodal address , not to mentioned out of the county, that transportation becomes the responsibility of the parent that moved. Any thought?

Its something you would have to take up with the courts.

No, it is not automacticly anyone's responsibility unless it is covered in the child custody agreement,

Time to go back to court to get visits modified.