Alex Neil's men didn't have to get into top gear to see off the Black Cats and in all honesty, the margin of victory could have been much greater.
Sean Maguire broke the deadlock five minutes into the second half with his fifth goal in four games, connecting with a Paul Gallagher free-kick to send a diving header past keeper Lee Camp.
The Irishman completing 90 minutes for the first time since his four-month lay-off with a serious hamstring injury was another bonus on a freezing cold day on Wearside.
Callum Robinson netted the second in the 63rd minute, his goal coming three minutes after Sunderland defender Jake Clarke-Salter had been shown the red card for his second booking of the afternoon.
There were few scares for North End when protecting the lead, the home side offering little and looking destined for a second successive relegation.
More than 2,200 PNE supporters had made the trip to the North East in difficult conditions, an eighth away win of the season their reward.
The North End side had shown three changes from the one beaten by Fulham, with Chris Maxwell, Paul and Josh Earl coming into the starting XI.
Maxwell replaced Declan Rudd who was attending the birth of his second child, Earl took over from Greg Cunningham who had a hamstring strain, while Gallagher came in for Daniel Johnson in midfield.
The first-half play saw Preston on the front foot and bossing possession, with Sunderland relying heavily on the break and looking lively when they moved the ball that way.
Early on, Ben Davies made a fine sliding tackle on Josh Maja inside the box after the ball had been worked to him from the left-wing.
Maxwell was off his line to block at the feet of Joel Asoro in the 16th minute, the ball running out for a corner which North End cleared.
A fine ball from Robinson split the home defence to play in Tom Barkhuizen at the other end, amp nicking the ball away from the North End winger just as he was about to connect.
A low angled shot from Bryan Oviedo was saved comfortably by Maxwell diving to his left, Asoro's pass having found Oviedo on the left side of the box.
North End had a good spell of pressure in the run-up to the break as they looked to turn possession into something more meaningful.
Gallagher's free-kick from the right channel in the 35th minute found Davies in the box but the centre-back's header cleared the bar.
Ben Pearson drove a shot from the edge of the 'D' too high, then Huntington should have scored when he met a Gallagher corner but sent a header over the bar from six yards out.
Just after the interval, Preston worked the ball across the pitch to Earl on the left, the teenager's low cross missed by inches by Robinson as he slid into the six-yard box.
North End took the lead in the 50th minute, a foul on Barkhuizen earning them a free-kick 25 yards out.
Gallagher whipped it right-footed over to the far post where Maguire was unmarked to send a diving header across the keeper into the net.
Not long after they had a chance to double their lead but Robinson missed his kick in front of goal after Browne had put a low ball into the middle.
Sunderland were reduced to 10 men on the hour when Clarke-Salter was shown a red card.
The on-loan Chelsea youngster had been booked in the first half for a foul on Barkhuizen and when he pulled back Browne as the midfielder broke through midfield, referee Darren Bond showed him a second yellow and then red.
Within three minutes North End had made their extra man count as they found the net a second time.
Barkhuizen got possession down the right channel and chipped a cross into the middle, the unattended Robinson having the simple task of heading past Camp from six yards.
In the 76th minute, a free-kick from Sunderland substitute Kazenga Lualua was tipped over the bar by Maxwell diving to his left.
North End toyed with the hosts for the final 10 minutes, dominating possession with some short passing.
They almost got a third goal on the break in the 89th minute, Pearson's pass finding Maguire in space on the left who in turn played in substitute Daniel Johnson.
DJ took the ball round keeper Camp but from a narrow angle saw his shot cleared off the line by Oviedo.
Sunderland: Camp, Matthews, Clarke-Slater, O'Shea, Kone, Oviedo, Honeyman (Lualua 69), Cattermole, Ejaria (McNair 76), Asoro, Maja (Fletcher 63). Subs (not used): McManaman, McGeady, Robson, Stryjek.
PNE: Maxwell, Fisher, Huntington, Davies, Earl, Pearson, Gallagher (Johnson 72), Robinson (Harrop 86), Browne, Barkhuizen (Bodin 86), Maguire. Subs (not used): Clarke, Woods, Moult, Hudson.
Referee: Darren Bond (Wigan)
Attendance: 28,543 (2,277 PNE)