A test stand for an internal combustion engine (1) is equipped with a drive (2) and/or load system (3), a force transmission device (4) with a system (5) for a non-destructive and play-free automatic coupling of the internal combustion engine (1) to the drive (2) and/or load system (3), and a sensor and evaluation system for automatically collecting and evaluating measurement variables. The system (5) for a non-destructive and play-free automatic coupling of the internal combustion engine includes an internally toothed and longitudinally slotted clamping sleeve (12) for receiving an element (13) of the internal combustion engine (1) in a form and force fitting manner, wherein the outer side of the clamping sleeve (12) is conically formed and interacts with a clamping collet (10) which is conically formed on the inside.