A drilling machine for boring holes in a slab having a hole formed therein includes a main frame to which a drill gang assembly is rotatably and telescopingly mounted. The drill gang assembly includes a drill support frame supporting a plurality of drills in parallel spaced alignment. The drill gang assembly is mounted on a mast which may be rotated three hundred and sixty degrees relative to the main frame about a vertical axis up to at least one hundred and eighty degrees. The mast slides laterally relative to the main frame and the wheels supporting the main frame telescope laterally so the wheels can be supported on an adjacent lane or shoulder when the drill gang assembly is supported over a hole extending the width of a lane of a road forming by the slab.