Aggressive pace bowler Sears claimed 5-34 to follow his five-wicket bag in Hamilton, with four of his victims falling to short-pitched deliveries.
Fellow seamer Jacob Duffy, who was a handful in both series, took 2-40, including the wicket of Mohammad Rizwan for 37 in the 33rd over to effectively end the tourists’ hopes of victory.
Babar Azam top-scored with 50 off 58 balls while opener Abdullah Shafique ground out a sluggish 33 off 56.
Pakistan’s innings began badly when opener Imam-ul-Haq was forced to retire hurt for one, having been struck on the jaw by a fielder’s throw when attempting a quick single.
Earlier, Rhys Mariu scored a maiden half-century after New Zealand were asked to bat first, with the start of the match delayed for two hours because of a wet outfield.
Opener Mariu, playing just his second international match, scored a composed 58 off 61 balls, featuring six fours and two sixes.
A number of New Zealand middle-order batsmen made starts but didn’t press on for big scores until captain Michael Bracewell produced a flashy 59 at the death.
Bracewell struck six sixes in his 40-ball knock before being caught off the last ball of the innings bowled by Akif Javed.
Seamer Javed took 4-62 off his eight overs although Naseem Shah was arguably the best of the Pakistan bowlers, taking 2-54 and bowling with good pace and movement.