Melt fracture of batches of a styrene-butadiene (SBR1502) rubber compound filled with 30 phr N330 carbon black produced at various mixing times was investigated in terms of surface texture wavelength, As mixing time is reduced the wavelength and the severity of surface disruption increases, The wavelength is controlled strongly by the effective volume fraction of filler or state-of-mix and by shear rate, A mechanism for melt fracture of the SBR compound has been proposed, based on average energy at the extrudate surface. In order to maintain wall slip and fracture at the extrudate surface, the average energy at the extrudate surface must be higher than the critical energy at the extrudate surface.