There were no changes in the class leaders, but plenty of drama following four hours of competition at Daytona.

Christian Fittipaldi took the overall lead at the four-hour mark of the Rolex 24 in the No.5 Mustang Sampling Cadillac DPI-V.R, following the end of a round of pit stops. Pipo Derani had worked his way up to second before cutting a right-rear tire on the No.22 ESM Nissan Onroak DPi. The team replaced bodywork following a slow trip back to the pits, resulting in five lost laps and 17th position. By the four-hour mark, Johannes van Overbeek was up to 16th, four laps in arrears.

• Hour 4 results

Ryan Dalziel was second in the No.2 Tequila Patron ESM Nissan Onroak DPi, followed by Jordan Taylor in the No.10 Konica Minolta Cadillac and Graham Rahal in the No.7 Acura Team Penske ARX-05.

The fourth hour ran caution-free, with nine cars completing all 137 laps.

Dirk Mueller continued to pace GTLM in the No.66 Ford GT, but Frederic Makowiecki worked the No.911 Porsche 911 RSR up to second, followed by Scott Dixon in the No.67 Ford.

Luca Stolz continued to lead GTD in the No.33 Mercedes-AMG GT3, followed by Christopher Mies in the No.99 Montaplast Audi R8 LMS.

Sunoco Whelen Challenge winner Stuart Middleton was assessed a stop-and-go penalty for a nudge to the No.6 Acura ARX-05 of Simon Pagenaud while battling for third position. He fell back to sixth in the No.31 Whelen Engineering Cadillac DPi-V.R after serving the penalty.

Later in the hour, Rene Rast cut a left-rear on the No.77 Mazda Team Joest RT-24P. That car, which experienced gearbox issues in Hour 2, is now 14 laps behind.

RACER.com’s coverage of the Rolex 24 At Daytona is presented by Forgeline Motorsports, manufacturers of custom made-to-order lightweight forged aluminum street and racing performance wheels.