VARIABLE HEIGHT GROOVES IN MULTIPLE WEAR LAYER TREADS FOR RETREADED TIRES

Particular embodiments of the present invention include multi-wear layer treads having variable depth grooves for retreaded tires, retreaded tires, and methods of forming retreaded tires. In particular embodiments, such multi-wear layer tire treads include a thickness bounded depthwise by a top side configured to engage a ground surface during tire operation and a bottom side configured for attachment to a tire carcass, the thickness extending laterally between opposing side edges and longitudinally in a lengthwise direction of the tread. Such tread may further include a top groove extending a variable depth into the tread thickness from the top side, the top groove having a groove bottom that varies depthwise within the tread thickness to form multiple wear layers. In other embodiments, top grooves may or may not be variable depth grooves, while the tread further include a bottom groove extending a variable depth into the tread thickness from the bottom side.