The first free practice session of the 6 Hours of Shanghai weekend saw the cars begin the 90-minute session on a wet track after early morning rain.
The track remained damp throughout the practice session that saw the no8 Toyota Gazoo Racing TS050 Hybrid top the time sheets with Sebastien Buemi setting a 1m54.768 lap, 1.5 seconds ahead of the no7 Toyota and over four seconds ahead of the rest of the field headed by the no17 SMP Racing BR1-AER, with Matevos Isaakyan posting a 1m58.880 lap.
BMW Team MTEK were that fastest of the 11 LMGTE Pro entries, the German manufacturer topping the time sheets ahead of Porsche and Aston Martin. Martin Tomczyk set a 2m09.830 lap in the no81 BMW M8 GTE, over two seconds ahead of Richard Lietz in no91 Porsche 911 and the no97 Aston Martin Vantage of Maxime Martin. The no64 Corvette Racing C7.R set a best time of 2m13.41 to finish the first session 7th quickest on the American manufacturers FIA WEC first race outside of the 24 Hours of Le Mans.
The no37 Jackie Chan DC Racing Oreca was the fastest of the seven car LMP2 field after Jazeman Jaafar set a 2m02.923. The 6 Hours of Fuji race winner finished 0.6 seconds ahead of the no29 Racing Team Nederland Dallara of Nyck de Vries and a further 0.7 seconds ahead Loic Duval in the no28 TDS Racing Oreca-Gibson.
Aston Martin led the way in the LMGTE Am category with the no90 TF Sport Vantage posting the fastest lap in the wet conditions. Charlie Eastwood posted a 2m11.764, 1.7 seconds ahead of the no77 Dempsey Proton Racing Porsche of Matt Campbell and 1.8 of the no61 Clearwater Racing Ferrari.