The invention relates to a pneumatic truck tire, particularly a bus tire, with a tread of a cap/base configuration comprised of a circumferential outer tread cap rubber layer and an underlying tread base rubber layer. The outer tread cap rubber layer is configured with lugs, particularly circumferential ribs with circumferential grooves between the ribs. A tread groove-containing rubber block tire component which joins the tread base rubber layer and extends radially outward into the outer tread cap rubber layer.