The Washington Post noted that "the hooks to songs such as 'Machine Action' and 'Crazy Love' recall Nirvana, a perhaps unwelcome but nonetheless accurate comparison."[9]Billboard wrote that Gruntruck "may not have the musical moxie to push them above [Seattle's] wall of grunge, but they're capable of dishing out some decent songs with coherent melodies, effective arrangements and a good measure of passion."[6]
USA Today praised the production of Endino, writing that "most of the ditties encourage a unique brand of booty shakin', not headbanging," while noting that "guitarist Tommy Niemeyer ... still rips out E string-based metal from opening cut 'Tribe' to the final tune, 'Push'."[10]The Seattle Times deemed the album "grunge-meets-psychedelia."[11]