Morphometric analyses of carnivoran dentition (e.g. linear measurements of length and width) have been used to separate taxa according to broad dietary categories. While these studies generally discriminate the diets of carnivorans at the family level, analysis of a previously underappreciated qualitative dental feature of carnivorans, premolar intercuspid notches (the notches between the accessory cuspids), allows discrimination of the carcass-processing abilities within families. In this study, intercuspid notch characteristics are scored, and the high correlations of the interspecific variation with the detailed carcass-processing abilities of a broad range of extant taxa allows for substantial discriminatory inference of the carcass-processing abilities of the Plio-Pleistocene carnivores of South Africa. Application of the scoring method to extinct carnivorans suggests that the Plio-Pleistocene hyaenid Chasmaporthetes was hypercarnivorous, similar to modern felids, and not durophagous, like the confamilial modern hyenas. Most surprisingly, and contrary to current hypotheses, these analyses suggest that the sabertooth felids were less carnivorous than modern felids. This new technique identifies subtle dietary differences between closely related species that are not captured by other means of dental-dietary inference.