O’Keeffe continued a strong start to the weekend for the GRM Renaults, beating fellow Megane driver and Practice 1 pacesetter James Moffat by three-tenths.
Jordan Cox then made it an GRM sweep of the top three places in his Alfa Romeo, while the squad had four entries in the top five courtesy of Jason Bargwanna (Peugeot) in fifth.
Michael Caruso (GRM Alfa Romeo) and Lee Holdsworth (Ashley Seward Motorsport Alfa Romeo) rounded out the Top 10.
Series leader Chaz Mostert was just 13th fastest in his MPC Audi while title rival Aaron Cameron was 17th in his GRM Peugeot.
Qualifying and Race 1 will take place tomorrow.
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