The tire has a crown part with sidewalls that end in beads. The crown part has a tread and a crown reinforcement. The crown reinforcement has protective, working and additional reinforcements. The protective reinforcement has a protective layer with elastic metal reinforcers which form an angle at least equal to 10°. The working reinforcement has working layers with crossed metal reinforcers and forming, with the circumferential direction, an angle at most equal to 60°. The additional reinforcement has a layer with an axial width at most equal to 0.9 times the shortest of the axial widths of the working layers and comprising metal reinforcers which form an angle at most equal to 25°. A tread pattern design of the tread has circumferentially oriented grooves. The mean axial distance between the two grooves closest to the equatorial midplane is greater than the maximum axial width of the additional reinforcement.