My buddy's 1970 big block motor seized up last weekend when he was driving about 80 mph (on L.A. freeway of course). He lost oil pressure and the motor seized up (unfortunately didn't hear the knocking because all his windows were rolled down). He had oil pressure problem earlier and just replaced the oil pump. His mechanic told him it may have been a bearing problem. I always thought bearings only received oil, and would have nothing to do with the loss of oil pressure, not enough to seize the motor anyway. If he spun a bearing, would this cause enough loss of oil pressure to seize the motor?