The invention provides for a heavy
truck tire
tread (2) having a longitudinal direction, a lateral direction and a thickness direction, said
tread having a ground-engaging surface and comprising at least four longitudinal grooves, the at least four longitudinal grooves (3, 4, 5, 6, 7) comprising two open grooves (4, 6) and at least two partially hidden grooves (3, 5, 7), the partially hidden grooves comprising open portions and duct portions alternated along the longitudinal direction of the
tread, said at least four longitudinal grooves defining two shoulder ribs, two intermediate ribs and atleast one center rib, wherein the shape, size and position of the grooves are such that for any section of tread of any given section length L between 12 mm and 40 mm, the
percentage difference in rubber
mass of a rib section compared to a respective neighboring rib section of the same section length L in the same rib is less than a maximum
percentage difference, wherein the maximum
percentage difference for a shoulder rib is Ds(%) = 50 / L(mm), the maximum percentage difference for an intermediate rib is Di(%) = 70 / L(mm), and the maximum percentage difference for a full tread section is Da(%)= 40 / L(mm).