A battle for the GTLM victory between the Ford GTs saw Ryan Briscoe and the No. 67 car take the win.
After being in contention in the early going, Spirit of Daytona Racing's new Cadillac DPi retired from the Rolex 24 with 15 hours still on the clock.
The two Cadillac DPi-V.Rs fielded by Action Express Racing entered the final quarter of the Rolex 24 leading overall.
Two Acuras and four Cadillacs dueled at the front of the field as the Rolex 24's halfway mark arrived.
Continental Tire has blamed brave setups by teams for the right-rear blowouts wreaking havoc on the Rolex 24.
One quarter into the Rolex 24, Mike Conway led overall in Action Express Racing's No. 31 Cadillac DPi.
Three Cadillac DPi-V.Rs led overall entering the second hour of the Rolex 24.
Track facts, entrant facts, the weather forecast, session results and more for the 2018 Rolex 24 at Daytona.
The final session ahead of the Rolex 24 race itself was topped by Mike Conway and the No. 31 Cadillac DPi-V.R.
England-based United Autosports will field Bruno Senna, Phil Hanson and a third to-be-announced driver at Sebring, Watkins Glen and Road Atlanta.