An attachment assembly for securing ripper teeth to an earth excavation device which comprises a substantially "J"-shaped ripper shank defining a lower forwardly projecting tapered end portion for carrying the tooth, an upper end portion for attachment to the excavation device and a front end wall defining a forwardly projecting elongated securement rib. An elongated wear cap extends over the lower portion of the front end wall of the shank and defines a tapered front digging surface, a lower tapered end portion which merges into the forwardly projecting tapered end portions of the shank and with said portion extends into a cavity in the base of the ripper tooth. The rear surface of the wear cap defines an open channel therein adapted to receive the securement rib on the front end wall of the shank upon the wear cap being transversely slided thereover. A substantially U-shaped securement member is secured to the upper portion of the wear cap and extends about the upper portion of the wear cap and oppositely disposed portions of the side walls of the shank so as to prevent any relative lateral movement between the wear cap and shank.