An assembly for joining ends of a drive track of an endless track drive system includes at least one connector member or connector member belt situated within the endless drive track, one or two retaining rods situated between abutting ends of the endless drive track, and a master link with a one-piece upper part and a one-piece lower part. The connector member(s) or connector member belt(s) is situated within the endless drive track in such a way that substantially parallel lengths of the connector member(s) or connector member belt(s) extend longitudinally of the endless drive track and loops of the connector member(s) or connector member belt(s) extend from ends of the endless drive track. The loops extending from abutting ends of the endless drive track are looped around an individual retaining rod, or two different retaining rods, and the retaining rod(s) and loops are sandwiched between the upper and lower master link parts by a fastening device which holds the upper and lower master link parts to one another. The retaining rod(s) is circumferentially grooved and connector member loops are disposed within the groove(s) so as to lie below the outer circumferential surface of the retaining rod(s), such that compression is exerted by the master link upon the retaining rod(s) and not upon the connector member loops. The simplified, high strength joint assembly can be utilized for interconnecting one or more drive track modules to form an endless drive track.