Abstract: The invention relates to a pneumatic rubber tire having an outer, circumferential tread wherein said tread has a tread configuration comprised of significantly spaced apart, raised lugs designed to be shock absorbingly ground engaging. For such tire, it is intended that, in the field, normally few tread lugs actually engage the ground at any one time in a manner that individual lugs have a relatively significant shock absorbing responsibility. Said tread and associated tread lugs are comprised of a shock dampening closed cellular rubber composition. The rubber for such cellular rubber composition for said tread of spaced apart lugs is comprised of conjugated diene-based elastomers or comprised of elastomers selected from butyl rubber, halogenated butyl rubber or brominated copolymer of isobutylene and paramethylstyrene rubber. Said butyl rubber is a copolymer of isobutylene and a minor amount of a diene monomer such as isoprene.