A power drive unit for propelling cargo containers and pallets in a desired direction over a plurality of cargo deck roller elements includes an elongated yoke having a pivot end and an opposite end. The pivot end is pivotally connected to a deck support structure. A drive roller is rotatably mounted to the yoke. At least one resilient member is disposed between the opposite end of the yoke and the support portion of the deck structure. A drive motor coupled to the drive roller selectively rotates the drive roller in two opposed directions. A reaction member connected to the drive motor is at least partially movably engaged with the deck support structure to permit at least some pivotal movement of the yoke, and to substantially prevent rotation of the drive motor relative to the yoke.