With tyres in short supply, both 15-minute sessions were largely void of action apart from the final five minutes.
The one-lap wonder in the first session was Whincup, the Red Bull Holden braving the slightly damp conditions to grab the first pole on offer with a 1m28.075s.
Whincup's teammate Shane van Gisbergen was second fastest, followed by DJR Team Penske pair McLaughlin and Coulthard.
Cam Waters was best of the rest in fifth, while Nick Percat kept his strong weekend going with sixth.
Chaz Mostert qualified seventh, with Jack Le Brocq eighth, his best result since joining Tickford Racing.
The second session saw a record-breaking performance from McLaughlin.
The reigning champion lowered the category benchmark he set in qualifying in 2018, a 1m.27.919s now the fastest Supercars lap around the Sydney circuit.
Whincup backed up his pole with second, the top three unchanged as van Gisbergen qualified third.
Lee Holdsworth was fourth for Tickford, with Todd Hazelwood the surprise of the session with fifth.
Waters was sixth, Coulthard seventh and Percat eighth.
Race 2 qualifying results
|1||88|| Jamie Whincup ||1'28.075|
|2||97|| Shane van Gisbergen ||1'28.087||0.012||0.012|
|3||17|| Scott McLaughlin ||1'28.140||0.064||0.052|
|4||12|| Fabian Coulthard ||1'28.554||0.479||0.414|
|5||6|| Cameron Waters ||1'28.616||0.540||0.061|
|6||8|| Nick Percat ||1'28.645||0.569||0.028|
|7||25|| Chaz Mostert ||1'28.657||0.581||0.012|
|8||55|| Jack Le Brocq ||1'28.861||0.785||0.204|
|9||7|| Andre Heimgartner ||1'28.954||0.878||0.092|
|10||9|| David Reynolds ||1'28.972||0.896||0.018|
|View full results|
Race 3 qualifying results
|1||17|| Scott McLaughlin ||1'27.919|
|2||88|| Jamie Whincup ||1'28.011||0.092||0.092|
|3||97|| Shane van Gisbergen ||1'28.123||0.204||0.111|
|4||5|| Lee Holdsworth ||1'28.411||0.491||0.287|
|5||14|| Todd Hazelwood ||1'28.441||0.522||0.030|
|6||6|| Cameron Waters ||1'28.445||0.526||0.004|
|7||12|| Fabian Coulthard ||1'28.464||0.545||0.018|
|8||8|| Nick Percat ||1'28.496||0.576||0.031|
|9||9|| David Reynolds ||1'28.563||0.644||0.067|
|10||2|| Bryce Fullwood ||1'28.639||0.720||0.076|
|View full results|