A surface-mounted lift, powered by an electric motor, is bolted to the garage floor. A hydraulic pump pushes fluid in hydraulic cylinders to lift the vehicle. Types of surface-mounted lifts include two-column and four-column lifts.
Two-Column Lifts. The two-column drive through frame engaging lift is often called a two-post lift. Two-post lifts have synchronized lift arms that ride up each column evenly. This type of lift is commonly used for doing under-the-car service work. Since the lift contacts the frame, and not the wheels, it is an ideal setup for completing tire rotations, brake inspections, and suspension work. It is also used for doing undercarriage work on exhaust systems and performing oil changes. By far, the two-post lift is the most popular type of surface-mounted automotive lift.
Four-Column Lifts. The four-column drive on lift is often called a four-post lift. Four-post lifts have runways. Once the vehicle is driven onto the runways, it is raised by its tires exposing the underside. This type of lift is most common in muffler and oil change shops. It is relatively safe and easy to use. The main disadvantage is the inability to perform services that require the removal of wheels without adding special adapters to lift the vehicle off the runways. These special adapters, called rolling lift jacks, are available from many manufacturers.