An undercarriage including a track roller frame, various guiding components connected to the track roller frame, and an endless track engaging the guiding components, the guiding components of the undercarriage including a drive sprocket, an idler, a plurality of rollers, a plurality of track guidings, and a plurality of carriers, wherein the endless track includes a link assembly, the link assembly comprising: a plurality of pairs of inner track links, each pair of inner track links including two track links connected to one another in laterally spaced relationship; a plurality of pairs of outer track links, each pair of outer track links including two track links connected to one another in laterally spaced relationship, wherein each pair of outer track links is pivotally connected to two of said pairs of inner track links with the links of each pair of outer track links disposed laterally outward of the links of each pair of inner track links; and wherein outer side surfaces of said plurality of pairs of outer track links form first and second discontinuous outer roller guide surfaces of the link assembly with gaps large enough that outer guiding features of any given roller do not necessarily remain in engagement with outer guide surfaces at all times; or wherein inner side surfaces of said plurality of pairs of inner track links form first and second discontinuous inner roller guide surfaces of the link assembly with gaps large enough that inner guiding features of any given roller do not necessarily remain in engagement with inner guide surfaces at all times; and wherein each roller (34, 35) includes two roller treads (154, 156) for engaging roller rails of the link assembly; each roller (34, 35) has provisions for providing lateral guidance between the rollers (34, 35) and the track and axially outward of the roller treads (154, 156); and each roller (34, 35) includes a pair of outer guide flanges (158, 160) extending radially outward of the roller treads (154, 156), respectively, wherein, in addition to the outer guide flanges (158, 160), one first of the rollers has a single center guide flange disposed between the roller treads (154, 156); and wherein one second of the rollers lacks the central guide flange and includes a central groove in lieu of the central guide flange. a plurality of pairs of inner track links, each pair of inner track links including two track links connected to one another in laterally spaced relationship; a plurality of pairs of outer track links, each pair of outer track links including two track links connected to one another in laterally spaced relationship, wherein each pair of outer track links is pivotally connected to two of said pairs of inner track links with the links of each pair of outer track links disposed laterally outward of the links of each pair of inner track links; and wherein outer side surfaces of said plurality of pairs of outer track links form first and second discontinuous outer roller guide surfaces of the link assembly with gaps large enough that outer guiding features of any given roller do not necessarily remain in engagement with outer guide surfaces at all times; or wherein inner side surfaces of said plurality of pairs of inner track links form first and second discontinuous inner roller guide surfaces of the link assembly with gaps large enough that inner guiding features of any given roller do not necessarily remain in engagement with inner guide surfaces at all times; and wherein each roller (34, 35) includes two roller treads (154, 156) for engaging roller rails of the link assembly; each roller (34, 35) has provisions for providing lateral guidance between the rollers (34, 35) and the track and axially outward of the roller treads (154, 156); and each roller (34, 35) includes a pair of outer guide flanges (158, 160) extending radially outward of the roller treads (154, 156), respectively, wherein, in addition to the outer guide flanges (158, 160), one first of the rollers has a single center guide flange disposed between the roller treads (154, 156); and wherein one second of the rollers lacks the central guide flange and includes a central groove in lieu of the central guide flange.