David Connolly returned to haunt Wolves as West Ham pulled off an FA Cup upset against the Premiership strugglers at Molineux.
Connolly, who scored seven goals for Wolves during a loan spell in 1998 and who was a recent transfer target of manager Dave Jones, grabbed United's third goal as the Upton Park outfit eased into the fifth round.
In the process United ended Wolves' 11-game unbeaten run at home that had stretched back to last September and included a win against Manchester United and a draw with Liverpool in their previous two matches.
United sealed their success after a scintillating first-half display that saw Brian Deane, Marlon Harewood and Connolly all on the mark for Alan Pardew's team.
Wolves' new Romanian international striker Ioan Ganea briefly gave them hope with his first goal for the club, but it proved no more than a consolation - leaving them to now focus solely on their battle for Premiership survival.
The writing was on the wall for Wolves as early as the fourth minute when the well travelled Deane fired United ahead with his fifth goal of the season.
The former Sheffield United marksman volleyed home from the edge of the area after Wolves had failed to fully clear a ball into the box from the impressive Michael Carrick.
United increased their lead in the 21st minute when Deane turned provider for Harewood.
Deane rose at the far post to head back a cross from Jon Harley with Harewood then volleying home from six yards.
Stung by the shock of falling further behind, Wolves reduced the deficit just two minutes later through Ganea.
He calmly slotted the ball past United keeper Steve Bywater from 12 yards after collecting a cross from Silas.
But his strike proved to be a rare moment of relief for Wolves who again found themselves trailing by two goals in the 32nd minute.
Matthew Etherington released Connolly and the Republic of Ireland international easily outpaced the Wolves right-back Oleg Luzhny before rifling his rising shot into the roof of the net to take his tally for the season to 11.
Wolves then wasted their best chance to grab a lifeline 23 minutes into the second half.
Ganea shot weakly at Bywater from close range following Colin Cameron's through ball and then substitute Leon Clarke fired the rebound wide when faced with an open goal.
Their misery was then summed up in the 87th minute when Cameron crashed his shot against the foot of the post from 14 yards.