Dishonest and deceptive.
I took my 2010 Honda Civic in for an oil change. The service manager told me I had to have synthetic oil to maintain my warranty. This is not true. I called the dealership to confirm this. The dealership did my first oil change and did not use synthetic oil. I feel this was simply an attempt to gouge the customer for a product they do not need. I will never take a vehicle back to these people for service.