A grill assembly for attachment to a trailer hitch includes a support post including a trailer hitch received segment having a trailer hitch received end and a grill mounting segment. A convertible grill includes a lower portion that has a back side, a front side, a first end, an open second end, and a bottom side. A charcoal grill insert has a first semicircular end, a second semicircular end, and an exterior wall extending between the ends. The charcoal grill insert can be inserted into the opening so that the convertible grill can be used as a charcoal grill. A propane grill insert has a first crescent end, a second crescent end, and an outside wall extending between the ends. The propane grill can be inserted into the opening and the convertible grill be used as a propane grill.