There were three practice sessions preceding the start of the race on Sunday, two on Friday and one on Saturday. The first two one-hour sessions were on Friday morning and afternoon. The third on Saturday morning lasted an hour.
Saturday afternoon's 65-minute qualifying session was divided into three groups. All three categories had 15-minute individual sessions, and regulations stipulated teams to nominate a single driver to qualify their cars. The competitors' fastest lap times determined the starting order with the grid arranged to put the Prototype and GTLM cars ahead of all GTD entries.
The result kept Curran and Nasr atop the Prototype Drivers' Championship with 299 points. Bennett and Braun advanced from third to second while Cameron and Montoya jumped from sixth to fourth. The result kept García and Magnussen atop the GTLM Drivers' Championship with 299 points, 9 points ahead of Briscoe and Westbrook. The result kept Sellers and Snow atop the GTD Drivers' Championship with 303 points, 6 points ahead of Legge. Cadillac, Ford, and Lamborghini continued to top their respective Manufacturers' Championships while Whelen Engineering Racing, Corvette Racing, and Paul Miller Racing kept their respective advantages in the Teams' Championships with one round left in the season.
Class winners are denoted in bold and ‡.
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The #5 Mustang Sampling Racing entry was involved in an accident on the opening lap of the race with the #66 Ford Chip Ganassi Racing and #911 Porsche GT Team entries. The car did not cross the start finish line and scored no points.
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