Sacrificial ribs for improved tire wear

A heavy duty tire, said tire having a tread, a carcass extending between spaced apart bead cores, a central crown area outside said carcass with a belt package for helping support said tread in contact with a supporting surface, wherein said tread comprises:

• a plurality of main ribs formed by main tread grooves extending generally circumferentially around an outer surface of the tire to form a main tread width over a tread surface for contacting the supporting surface;
• a sacrificial rib for contacting the supporting surface at each lateral side of the main tread width, said sacrificial rib separated from said main ribs by a narrow shoulder groove having a groove width such that said sacrificial rib contacts a first interior rib during straight ahead driving of a loaded tire;
• each of said sacrificial ribs has a surface width in the range of about 2.5 percent to about 12 percent of said tread width;
• each of said sacrificial ribs has an outer surface recessed from a transverse profile of said main ribs by a radial offset, said radial offset having a value in the range of about 0.5 millimeter to about 2.0 millimeters when the tire is new;
• and
• the edge of said main rib adjacent to each of said narrow shoulder grooves has a plurality of sipes extending horizontally from said narrow shoulder groove in a direction corresponding to the rotation direction of the tire at a lateral angle of about 15 degrees to 35 degrees and extending vertically at an angle inclined rearward from an outward normal to said tread surface of about 5 degrees to about 15 degrees.