Auto stocks surged Monday after PM Modi's Independence Day speech signaled sweeping GST reforms, with Maruti, Hero MotoCorp, and Ashok Leyland gaining 6-8%. Analysts expect the two-slab GST structure and lower auto tax rates to spark a consumption-driven rally, benefiting autos, FMCG, apparel, and retail. The overhaul aims to cut household tax burdens and ease SME compliance.