Equity benchmarks darted up to fresh lifetime highs on Tuesday, propelled by heavy buying in banking, finance and metal stocks amid supportive global cues. Rising for the second straight session, the 30-share BSE Sensex soared 403.19 points or 0.73 per cent to end at its lifetime peak of 55,958.98. On similar lines, the broader NSE Nifty surged 128.15 points or 0.78 per cent to its all-time closing high of 16,624.60.