After a scoreless first half, the Red Devils scored three times in 10 minutes to gain control of the match. Michael Owen and Park Ji-Sung also scored for the Premier League champions.
Kenny Mansally scored for New England to make it 2-1 in the 56th minute, but Machedo made it 3-1 on a behind-the-back pass from Carrick that sent him in all alone on Revolution goalkeeper Bobby Shuttleworth.
United started only four players from the lineup that began the Champions League final against Barcelona, with liberal substitutions that took Wayne Rooney out at halftime. Ashley Young made his United debut after joining the Red Devils from Aston Villa last month for a reported $27 million. He came out in the 67th minute with United leading 3-1.
The attendance was announced at 51,523 — the highest-attended club friendly in Gillette Stadium history — though the upper deck was empty and the lower bowl had several pockets of empty seats.
It was 0-0 after 45 minutes — a moral victory for the Revolution, who are in last place in the MLS Eastern Conference.
But Owen scored in the 51st minute when he took a leading pass from Carrick at Shuttleworth's right and, just steps away, aimed a low shot just under the goalkeeper's outstretched leg. Just three minutes later, Carrick set up Macheda on a give-and-go that allowed Macheda to get between two New England defenders.
In the 56th minute, New England's Benny Feilhaber was awarded a free kick just outside the penalty area. He aimed his kick to the left of the defensive wall, where it deflected off Mansally and into the net.
Macheda scored again in the 61st minute, converting a crossing pass from Rafael that made it all the way across the goal mouth. United made it 4-1 in the 80th when Gabriel Obertan spent several moments of razzle-dazzle on New England's Zak Boggs, freezing him with fancy footwork before dropping a soft pass to Ryan Giggs.
Giggs touched it toward the net for Park, who waited for Shuttleworth to commit before chipping the ball over him and into the net.