A guardrail crash absorbing assembly comprising: an elongated upstream rail panel having an upstream rail panel front portion and an upstream rail panel rear portion ; an elongated downstream rail panel having a downstream rail panel front portion and a downstream rail panel rear portion , said upstream rail panel rear portion and said downstream rail panel front portion being in side by side, overlapping relationship at a panel joint; an impact head structure operatively associated with said upstream rail panel and responsive to vehicle impact on the impact head structure to move said upstream rail panel rearwardly lengthwise along said downstream rail panel ; and a braking structure for dissipating kinetic energy of said upstream rail panel sliding along the downstream rail panel and absorb impact forces caused by vehicle impact on said impact head structure , said braking structure including friction slider structure at said panel joint and at least one cutting tooth located at said panel joint operatively associated with said friction slider structure for cutting and splitting said downstream rail panel responsive to vehicle impact on said impact head structure ; wherein said cutting tooth includes a cutting tooth portion having a cutting surface and a hook structure , the cutting tooth portion projecting through slots formed in said upstream rail panel and said downstream rail panel at said panel joint, and wherein said friction slider structure includes a traffic side slider attached to said upstream rail panel for restricting the upstream rail panel and downstream rail panel to prevent flaring thereof into traffic, and an inside slider mounted to the inside of the downstream rail panel . an elongated upstream rail panel having an upstream rail panel front portion and an upstream rail panel rear portion ; an elongated downstream rail panel having a downstream rail panel front portion and a downstream rail panel rear portion , said upstream rail panel rear portion and said downstream rail panel front portion being in side by side, overlapping relationship at a panel joint; an impact head structure operatively associated with said upstream rail panel and responsive to vehicle impact on the impact head structure to move said upstream rail panel rearwardly lengthwise along said downstream rail panel ; and a braking structure for dissipating kinetic energy of said upstream rail panel sliding along the downstream rail panel and absorb impact forces caused by vehicle impact on said impact head structure , said braking structure including friction slider structure at said panel joint and at least one cutting tooth located at said panel joint operatively associated with said friction slider structure for cutting and splitting said downstream rail panel responsive to vehicle impact on said impact head structure ; wherein said cutting tooth includes a cutting tooth portion having a cutting surface and a hook structure , the cutting tooth portion projecting through slots formed in said upstream rail panel and said downstream rail panel at said panel joint, and wherein said friction slider structure includes a traffic side slider attached to said upstream rail panel for restricting the upstream rail panel and downstream rail panel to prevent flaring thereof into traffic, and an inside slider mounted to the inside of the downstream rail panel . <EOS>