My understanding is that they only automatically use Mobil 1 when changing the oil in a car that is model year 1998 and newer.
I am sure they will use it if you request it, but be ready to pay through your teeth for it. The costs are reasonable if you change it yourself.
1999 Dodge Ram 2500 Cummins Diesel
2002 Harley-Davidson Fatboy
Merlin Extralight w/ Campy Record