Abstract: A prefabricated service bay typically constructed of fiberglass has a tank-like profile with an access opening for providing access to the underside of a vehicle. The prefabricated service bay is placed within an excavated hole within a vehicle service stall. The tank has a rounded section normal to the longitudinal axis of the bay. Drainage fill, such as pea gravel, is used between the bottom portion of the excavation and the bottom portion of the tank. A concrete cap is poured and cured over the top portion of the tank adjacent the opening. This poured and cured concrete serendipitously forms paired tracks for rolling placement of the wheels of a vehicle being serviced and additionally serves to key and maintain the service bay within the ground. Provision is made to provide a central standing area--preferably in the form of a raised platform--in the center bottom portion of the tank. Entrance and exit to the bay is provided through an end passageway with optional side staircase entry.