Leading the Old Trafford Christmas onslaught once again were United's old guard. Two goals for Paul Scholes, a dazzling display by Ryan Giggs and that characteristic Roy Keane steel proved too much for Palace.
The last month has seen the rejuvenation of Scholes.
Without a goal this season until a month ago, Scholes has now hit six in as many games.
Equally as important to United boss Sir Alex Ferguson has been the former England man's contribution in making goals for others - he was instrumental in two of his side's other efforts.
Giggs is also enjoying a revival, taking players on, beating them and providing vital service to his strikers.
He played a key part in two of United's goals and could easily have scored two himself.
Keane may not be the force he once was for the Red Devils, but he continually breaks down the opposition in midfield and only the brilliance of Palace goalkeeper Gabor Kiraly kept his name off the scoresheet.
United began like a little child faced with a huge sack of presents in the early hours of Christmas morning. They wanted a goal from every attacking package.
Scholes directed a spectacular overhead kick at Kiraly in the seventh minute and United should have been ahead seconds later.
Giggs picked out Darren Fletcher on the right side of the Palace box and he went down under a challenge from Danny Granville when he turned the Palace left-back.
Referee Steve Dunn pointed to the spot and in the absence of United's normal penalty taker, the injured Ruud Van Nistelrooy - out for up to six weeks with an Achilles injury - Wayne Rooney was entrusted with the resulting kick.
The England youngster stepped up, but his poor right- foot kick towards the bottom left corner of the net was saved by the diving Kiraly.
But the miss failed to dull United's spirit.
In the 22nd minute, Giggs found Keane on the edge of the United box and he worked the ball inside to Scholes, who sidestepped Ben Watson and scored with a sweet right-foot curling shot from the left edge of the six-yard box into the top far corner of the net.
Keane blazed a 25-yard shot over the Palace bar and the Eagles equalised after 27 minutes.
Wayne Routledge's corner into the centre of the United box was headed goalwards by Gonzalo Sorondo. The ball hit Palace striker Andy Johnson and rebounded to Granville, who scored with a left-foot shot from 12 yards.
Back came United, only to be foiled by Kiraly's brilliance.
First the Hungarian tipped over a screaming 25-yard shot from Keane, then he threw himself across his line to tip behind a ferocious effort from Scholes in the 35th minute.
The effort went for a corner from which Scholes drove the ball to the far post where Alan Smith outjumped the Palace defence to score with a fine header from six yards.
If the first half had begun well, the second started in sensational fashion.
With only a minute gone, Routledge fed Michael Hughes down the right and his cross into the centre of the box was headed home by the diminutive Joonas Kolkka, who was unmarked 12 yards out.
Parity remained for only two minutes as United regained the lead.
Kiraly blocked Rooney's close- range shot with his legs, but Palace failed to clear the danger.
Gary Neville crossed from the right and Scholes nipped in between Kiraly and Emmerson Boyce and, although the United man got a touch, the ball was turned into his own net by Boyce from close range.
United made it 4-2 seconds later.
Neville's long throw on the right was neatly headed on by Smith in the Palace penalty area and Scholes scored with a right-foot shot from six yards as he fell to the ground.
Giggs produced two glorious moments soon after.
His tremendous 52nd minute run ended with him blazing in a shot which was brilliantly turned behind by Kiraly and the Welshman produced an even better mazy 50-yard run soon after, culminating in a shot which thudded into the Hungarian's midriff.
Kiraly was fast becoming Palace's busiest player blocking a Keane shot with his legs and then denying Rooney by palming away his 25-yard shot at full stretch.
At the other end, United goalkeeper Roy Carroll made a glorious one-handed stop from Routledge's close-range effort.
But United were still not finished when they scored the cheekiest of their five goals in injury time.
Giggs teed the ball up for substitute John O'Shea from the left by-line and the unmarked Irishman scored with a nonchalant left-foot shot from six yards.
Man of the Match: Paul Scholes – The former England international is back to his best, with two goals and the starring role in United's midfield.