Abstract: A roller brake dynamometer includes shuttle wheels which engage the dynamometer rollers and are movable between raised and lowered ground engaging positions. The shuttle wheels may be rotated in the same or opposite directions to move the dynamometer forwardly, rearwardly or turn it about its own axis. A dynamometer transport trailer includes an endless conveyor chain running the length of the center of the tiltable trailer bed which includes a tongue engagable with the dynamometer frame for pulling the dynamometer on to and off of the trailer bed.