We usually have better success on Thursdays and Friday mornings, particularly if you have a big weekend event. You want to keep these weekend sale offers fresh in people's minds. We stay away from sending emails out on Friday afternoons though. People who work 9 to 5ish have given up on their work for the day and are already making plans for that night/the weekend. Even though some dealerships are not open on Sundays in some states, Sunday campaigns have also had some success seeing that Monday is one of the more busier days for the automotive industry.