It has had all of the services done on time. The 60K service was done at 55K. I don't know if the 60K service would include the spark plus and tranny

. It has has all of the service A's and service B's on time. I was thinking about changing the oil myself. What synthetic oil should I use for this? I will go ahead and do the tranny service anywaysin about a month and have the sparkplugs changed if they need changing. How much does it usually cost to have the tranny serviced?
Thanks