Contenders in both the LMP2 and GTE-Am classes have hit trouble with two-thirds of the 24 Hours of Le Mans complete.
Both the No. 32 United Autosports Oreca 07 Gibson and No. 98 Aston Martin Vantage GTE, which were each running second in class, have been wheeled to their garages with mechanical issues.
The Job van Uitert-driven Oreca, which made three consecutive five-lap stints, has suffered an oil leak.
It came after an intense battle with the sister No. 22 Oreca for the class lead through the overnight hours.
The No. 98 Aston of Ross Gunn, meanwhile, sustained rear suspension failure and also remains in the garage.
The issues have given the No. 22 United Oreca and No. 90 TF Sport Aston Martin clear sailing in LMP2 and GTE-Am, respectively.
Up front, the No. 8 Toyota TS050 Hybrid continues to lead, with Kazuki Nakajima holding a two-lap cushion over the No. 1 Rebellion R13 Gibson in second.
The sister Toyota, which was delayed by 30 minutes due to a turbo failure, still runs fourth in class, six laps down.
GTE-Pro continues to be paced by the No. 51 AF Corse Ferrari 488 GTE, although both Aston Martins have remained closely in contention.
The No. 91 Porsche 911 RSR-19 made two trips to the garage with power steering issues, the same gremlins that struck its sister car earlier in the race.
Both the No. 63 WeatherTech Racing Ferrari (damage from an accident) and No. 21 DragonSpeed Oreca (misfire) are among the latest retirements in what has been a relatively clean race on track since the halfway point.