Anaheim built a 3-1 lead in the first period on goals by Silfverberg, Rickard Rakell and Derek Grant.
Silfverberg finished off a 3-on-2 to give the Ducks a 1-0 lead at 2:28.
"It's been a little bit up-and-down," Silfverberg said of his season. "There is no better time of the year to get the confidence going."
McKenna made a left pad save on a breakaway by Corey Perry for his first save at 2:57, but the Ducks went on the power play and Rakell tied his NHL career high from last season with his 33rd goal at 6:33 for a 2-0 lead.
"We had a really good start," Ducks coach Randy Carlyle said. "We had lots of energy. We were really skating and had our feet underneath us. They're still an opponent that scares you because they have a transition game and a lot of skill on that side that can make you pay."
Methot scored for the first time since March 19, 2016 to make it 2-1 at 11:13. The Ducks increased the lead to 3-1 when Grant deflected a shot by Silfverberg with 20 seconds left.
Manson scored on a rebound off Getzlaf's shot to make it 4-1 at 4:36 of the second period.
"We turned the puck over at the top of both zones too many times, and we made mistakes in what we call critical ice," Dallas coach Ken Hitchcock said. "They took advantage of it."
Radek Faksa cut the lead to 4-2 off a deflection at 7:49, and Benn beat Miller over his left shoulder from the slot at 2:52 of the third to make it 4-3. It was Benn's 33rd goal of the season.
Cogliano scored with 5:25 left to make it 5-3, his fifth point in the past three games (three goals, two assists).
"They looked like a team that was getting ready for the playoffs," Hitchcock said. "That's what they looked like, and we looked like a team that still was trying, but they had details in their game that we didn't have."