The hosts won the first game in Melbourne by eight wickets and the second in Sydney by 83 runs to clinch the series, with the West Indies playing for pride.
But after Australia skipper Steve Smith won the toss and sent them in on a humid day, they crumbled to 86 all out in the 25th over against an attack missing Josh Hazlewood, Pat Cummins and Mitchell Starc.
In reply, Australia recorded their shortest successful run chase in the format with 259 balls remaining to cap a stunning capitulation by the Caribbean side.
“It was a good performance, the bowlers put it in the right areas and everything seemed to work out. One of those days where everything came off,” said Smith.
“It’s been good opportunity to expose a few players to international cricket and they’ve shown that they can play at this level.”
Explosive 21-year-old opener Fraser-McGurk showed his immense talent in only his second match with five fours and three sixes in an electric 41 before he was caught going for another big hit off Alzarri Joseph.
Aaron Hardie was the only other wicket to fall, caught behind for two off Oshane Thomas.
Josh Inglis blasted an unbeaten 35 while Smith was not out six.
Earlier, paceman Xavier Bartlett took 4-21 to go with the 4-17 he bagged on his debut in Melbourne. Fellow fast bowler Lance Morris grabbed 2-13 before leaving the field with a side strain.
“Our batting let us down. It did for the entire series,” said West Indies captain Shai Hope.
“We need to do some real soul searching to understand what’s needed in certain conditions. Can’t really put your finger on one thing, it comes down to mindset.”
Bartlett struck early with Kjorn Ottley trapped lbw for eight and, while Alick Athanaze and Keacy Carty steadied the ship, they were in survival mode, with just 36 runs coming from the opening 10 overs.
Their partnership ended when Morris was introduced and grabbed his first international wicket, courtesy of Marnus Labuschagne holding a spectacular diving catch at point to remove Carty for 10.
Hope needed a big score and drove Morris to the ropes, but he lasted just five balls before falling lbw to Shaun Abbott, leaving the visitors in trouble on 43-3.
Debutant Teddy Bishop soon followed for a duck, undone by the sheer pace of Morris whose fullish ball clattered the middle stump before he left the field midway through his fifth over.
Athanaze was the one shining light, making a battling 32 off 60 balls before mis-hitting a sweep off spinner Adam Zampa with Abbott collecting a simple catch.
Two more wickets in three balls left the West Indies reeling, with Romario Shepherd out for a golden duck to Bartlett and Matthew Forde run out after a comical mix-up with Roston Chase.
Bartlett then cleaned up the tail with two more wickets.