Mike Ruddock's injury-hit Six Nations champions defended bravely but were subjected to an attacking onslaught from the All Blacks and suffered a record home defeat.
Wing Gear scored his hat-trick in 20 minutes either side of half-time as Wales' lung-busting defensive effort took its toll.
Fly-half Dan Carter delivered another immense performance - he did not miss a kick all game and scored two tries to finish with a personal haul of 26 points.
Wales struggled to set any decent attacking platform and could only muster three points from the boot of Stephen Jones.
Wales were missing six key members of their Grand Slam-winning squad - British & Irish Lions Gethin Jenkins, Ryan Jones, Dwayne Peel, Gavin Henson and Tom Shanklin are injured while Martyn Williams attended his mother's funeral on Friday.
The All Blacks had rung the changes too, but by choice rather than circumstance. Prop Neemia Tialata and flanker Chris Masoe both made their Test debuts in a formidably strong side that included Lion-tamers Carter and Tana Umaga.
And the All Blacks powered forward from the kick-off and enjoyed virtually unbroken possession as they spent the entire first 10 minutes camped in red dragon territory. Wales defended aggressively and bravely.
They bettered New Zealand at the breakdown, forced the All Blacks into mistakes and restricted them to two Carter penalties in the first 16 minutes.
A quick counter-attack earned Stephen Jones the chance to pull a penalty back but Wales could not clear their lines well enough to relieve the pressure and the dam was always going to burst at some point.
Gear dived over for the first on 29 minutes after Chris Jack stole a Welsh lineout and then ran onto a superb ball from Carter to score his second just after the interval.
His hat-trick was completed four minutes later when he finished off a lightning backs move in the right corner.
The All Blacks may well find themselves in another row over dangerous tackling after Tony Woodcock up-ended Brent Cockbain.
Wales pushed on bravely but it was to no avail and the imperious Carter provided the coup de grace with two late tries.