Liverpool arrived at Upton Park knowing they needed to win to keep the title race alive and from the moment Gerrard broke the offside trap to score after just 76 seconds it never looked in doubt.
West Ham were slow out of the blocks and Liverpool were quick to make them pay as Fernando Torres sliced the Hammers back four open with a wonderful through ball that Gerrard latched onto before rounding Robert Green and rolling the ball into the empty net.
The second arrived in controversial circumstances as West Ham felt they should have had a free-kick outside the Liverpool penalty area for a foul on Luis Boa Morte but referee Alan Wiley played on and within moments the former Fulham man had pulled down Torres in the penalty area. Penalty was the decision and once again it was Gerrard that capitalised. For a split second it appeared that Green had denied the Liverpool skipper with a fine save but the England midfielder was on hand to tap home the rebound and double the lead on 37 minutes.
David Di Michele was presented with a glorious chance just before the break to get the Hammers back in the game but stumbled when one-on-one with Jose Reina, who was rarely troubled after that. Ryan Babel replaced Torres late on and rounded off the scoring with five minutes left after a sweeping Liverpool counter attack.
The win lifts Liverpool back to the top of the table on goal difference, Manchester United now have two games in hand though, while defeat damages the Hammers hopes of Europa League football next season.