Andy Welsh, Chris Brown and Julio Arca all scored to give Manager of the Month Mick McCarthy his seventh straight win.
The visitors' performance after the break made up for a dire first half in which Rangers had all the chances.
Hoops defender Danny Shittu looked to have ended Sunderland's winning streak when he put Rangers into the lead in the 22nd minute with a header from Martin Rowlands' corner.
But Welsh levelled the scores a minute into the second half when he beat his marker Marcus Bignot to fire in Stephen Wright's cross from eight yards out.
Then substitute Brown put the visitors in front 64 minutes into the match after Dean Whitehead had split open the home defence.
Arca sealed it by tapping into an open goal after Simon Royce had done well to deny Marcus Stewart by diving at the striker's feet.
But the first half could not have been more different for the visitors, who failed to register a single shot on target until their first goal.
Rowlands had gone close in the opening minute of the match when he latched on to Kevin Gallen's cross only to be denied by Black Cats keeper Thomas Myhre.
Stephen Elliott wasted the visitors' only first-half chance in the 33rd minute when he was left unmarked at the far post but headed across the goalmouth.
Winger Rowlands was forced off with a leg injury in the 35th minute, making way for Dean Sturridge's Rangers debut. But Sturridge's bow lasted less than half an hour before he was taken off for Jamie Cureton.
Paul Furlong, who is currently negotiating a two-year contract extension, could have doubled QPR's lead just before the break when he ran on to a perfectly weighted pass from Gino Padula.
The 36-year-old striker volleyed goalward, but Myhre kept it out with a diving save.
A minute later Georges Santos was could have added another for Rangers from Lee Cook's corner had he not headed into Sturridge.
Lee Cook went close to retaking the lead for Rangers in the 48th minute with an 18-yard shot which Thomas Myhre palmed away.