Crude oil prices dropped in Asian trade on Thursday after investors booked profits following a surge, near 17-month highs. New York's main contract, light sweet crude for delivery in May, shed 43 cents to 83.33 dollars a barrel. The New York contract had gained 1.39 dollars, yesterday, peaking at 83.85 dollars a barrel, a level near October 2008 highs, before paring back gains on a report which showed a larger-than-expected build in US crude stocks. Brent North Sea crude for May eased 39 cents to 82.31 dollars per barrel.