And a brace of goals from Carlos Tevez and a fine finish from Wayne Rooney ensured they avoided a potential banana skin against Roy Hodgson's Fulham and will now be in the hat for the last four of the world's oldest cup competition.
Fulham had not beaten United since 1964 and after Tevez opened the scoring on 20 minutes they never looked likely to do so again, with the visitors putting them to the sword with consummate ease.
But Fulham will not be the only club to have found United too hot to handle and they can concentrate on securing a mid-table finish in the Premier League, while Ferguson's side go from strength to strength.
Fulham had more than held their own in the early stages, with Andy Johnson going close.
But after withstanding heavy pressure, United demonstrated just why they are in contention for every major trophy by going in front.
And it was Tevez who did the damage, heading in at the far post after Rooney had flicked on Anderson's corner for his 11th goal of the season.
Rooney missed an open goal from Ji-Sung Park's cut-back, before Tevez showed him how it should be done by cutting inside and arrowing a wonderful drive into the top corner of Mark Schwarzer's net.
The belief drained out of Fulham as United turned on the style, with the only surprise being that it took them until five minutes into the second half to increase their lead.
In truth the hosts allowed the 23-year-old far too much time and space on the edge of the box, but it was still an exquisite finish as Rooney curled the ball around Schwarzer and into the far corner.
With the game all but over both sides rested players, but it was fitting that United should have the final word.
Again Fulham let themselves down, with Zoltan Gera playing a horrible cross-field pass that Park intercepted before cutting in and bending the ball home from just inside the box.