First post i was refered to this site by a friend. Thanks in advance for any replies. Last labor day i bought my first new vehicle. Leftover 2013 silverado z71. 5.3. Only thing i usually tow is a 3000 lb rig bass boat. I am wondering what would be advantages or disadvantages when the 2 years of free oil changes by dealer is over going from the dexos to full synthetic mobil 1.? Or should i just stay with om oil?