Is the service department open sundays

Yes

I'll start by saying yes they're open. Then I will add make an appointment. Then I will tell you that the address listed is non-existent. That Route 46 does not run through East Hanover. The closest that it comes is Pine Brook New Jersey New Jersey. However that location is basically for tires. However there is another location on Route 46 up the road and that is in Parsippany. It is full service Parts tires and mechanical work.

Yes but make an appointment online

Always better to make an appointment regardless of the day - you can do it online.

Yes. But you will have to book prior appointment as sunday they are very busy