In a tire, a shape index of a reference ground contact surface is not less than 1.20 and not greater than 1.50. In the tire, a tread includes a cap layer, an intermediate layer formed such that a loss tangent of the intermediate layer at 30° C. is less than a loss tangent of the cap layer at 30° C. and a base layer formed such that a loss tangent of the base layer at 30° C. is less than the loss tangent of the intermediate layer at 30° C. In the radial direction, the intermediate layer is disposed outwardly of the base layer and the cap layer is disposed outwardly of the intermediate layer. In a shoulder land portion of the tread, a thickness of the cap layer at a center of an axial width is less than a thickness of the cap layer on the shoulder circumferential groove side.

In a tire 2, a tread 4 includes a cap layer 38 forming a part of the outer surface of the tire 2, an intermediate layer 40 disposed inwardly of the cap layer 38 in the radial direction, and a base layer 42 disposed inwardly of the intermediate layer 40 in the radial direction. A loss tangent of the intermediate layer 40 at 30° C. is less than a loss tangent of the cap layer 38 at 30° C., and a loss tangent of the base layer 42 at 30° C. is less than the loss tangent of the intermediate layer 40 at 30° C. An outer end PC of the cap layer 38 is disposed outwardly of an outer end PB of the base layer 42 in the axial direction. In the radial direction, a position of the outer end PC of the cap layer 38 coincides with a position of the outer end PB of the base layer 42, or the outer end PC of the cap layer 38 is disposed inwardly of the outer end PB of the base layer 42.

An object of the present disclosure is to provide a tire having improved overall performance of fuel efficiency, breaking resistance, and abrasion resistance. The tire comprises a tread, wherein a cap rubber layer of an outer surface of the tread is formed of a rubber composition comprising a rubber component having a total content of 90% by mass or more of an isoprene-based rubber and a butadiene rubber and silica having a nitrogen adsorption specific surface area (N.sub.2SA) of 180 m.sup.2/g or more, wherein a total cis content in the butadiene rubber is less than 90% by mass, wherein a tan δ at 70° C. of the rubber composition of the cap rubber layer is less than 0.15, wherein the tread has circumferential grooves extending continuously in a tire circumferential direction and lateral grooves extending in a tire width direction, and wherein a ratio of a total area S2 of the lateral grooves to a total area S1 of the circumferential grooves (S2/S1) is less than 0.80.

A pneumatic tire is provided where a profile line in a tire meridian cross section of a center land portion defined by circumferential grooves and located on a tire equator is curved projecting outward in a tire radial direction. A carcass layer and a reinforcing layer include a recess portion curved projecting inward in the tire radial direction in a bottom region of the center land portion.

A pneumatic tire for use on trucks, the tire comprising: a tread which includes a belt reinforcement structure, the belt structure including a pair of working belts, wherein the angle of the working belts range from about 10 degrees to about 50 degrees, and wherein the first working belt has an angle of the reinforcements different that the angle of the belt reinforcements of the second working belt. The belt package further includes a low angle belt that is preferably positioned between of the working belts. The pneumatic tire further includes a tread having a groove reinforced with a tread compound having a tensile at break greater than 18 MPa, and an elongation at break greater than 450%.

In a tire, each of first and second circumferential grooves include groove portions arranged discontinuously in a row in a circumferential direction. The groove portions are arranged in a staggered manner in the circumferential direction. A distance D1 from an equatorial plane to a center line of the first circumferential groove and a distance D2 from the equatorial plane to a center line of the second circumferential groove satisfy 0.90≤D2/D1≤1.10. A maximum groove width W1 of the groove portion of the first circumferential groove and a maximum groove width W2 of the groove portion of the second circumferential groove satisfy 0.90≤W2/W1≤1.10. A maximum circumferential length L1 of the groove portion of the first circumferential groove and a maximum circumferential length L2 of the groove portion of the second circumferential groove satisfy 0.90≤L2/L1≤1.10.

A tire includes a mounting direction indicator that indicates a tire mounting direction with respect to a vehicle. The tire includes a first circumferential groove and a second circumferential groove extending intermittently or continuously in a tire circumferential direction. Additionally, the second circumferential groove is located further on an inner side than the first circumferential groove in a vehicle width direction in a state in which the tire is mounted on a vehicle. Additionally, a groove volume V1 of the first circumferential groove and a groove volume V2 of the second circumferential groove have the relationship V1<V2.

A tire includes a mounting direction indicator indicating a tire mounting direction with respect to a vehicle. Additionally, the tire includes a first circumferential groove and a second circumferential groove extending intermittently or continuously in a tire circumferential direction. Additionally, the second circumferential groove is located further on an inner side than the first circumferential groove in a vehicle width direction in a state in which the tire is mounted on a vehicle. In addition, a distance D1 from the tire equatorial plane to the groove center line of the first circumferential groove and a distance D2 from the second circumferential groove to the groove center line have the relationship D1<D

In a pneumatic tire, a tread average thickness A in a tire width direction region of a center land portion where a center cover layer is disposed, a tread average thickness B in a tire width direction region of the center land portion where the center cover layer is not disposed, and a tread average thickness C in tire width direction regions where second land portions located further on an outer side than the center land portion in a tire width direction and adjacent to the center land portion are defined and formed satisfy a relationship A<B<C.

Provided is pneumatic tire in which a land portion includes a width direction sipe extending in a tread width direction, the width direction sipe includes, in a cross section along a depth direction, a linear portion extending from an opening of the width direction sipe toward a bottom of the width direction sipe, and a bent portion connected to the linear portion, bending and extending from a connecting portion with the linear portion to the bottom of the width direction sipe, and the linear portion of the width direction sipe has a length in the depth direction increasing as the linear portion extends from a center portion of the width direction sipe in the tread width direction toward an end portion in the tread width direction.