As for what the dealer charges for Mobil 1.......
I began using Mobil 1 at my first FSS oil change at 12,000 miles even before the bulletin came out to get away from dino oil. I always put a case and a half in the trunk before heading to the dealer and then one day I forgot. Do it once and I guarantee you will never forget again. $9 per quart at nearly 8 quarts.
Do the math.