Hour 18 ended with the #2 Audi of Treluyer in the lead with the top three covered by less than 28 seconds.

The hour started under safety car conditions after an incident between the GTE Pro Corvette of Magnussen and the GTE Am Porsche of Horst Felbermayr Sr.

At the start of the hour both the #8 and #7 Peugeot pitted while the #2 Audi swapped drivers, as Lotterer jumped out as Treluyer jumped in. There was a spin for #35 Da Rocha in his LMP2 ORECA 03-Judd BMW who nearly collected the #9 Peugeot of Pagenaud.

The #9 Peugeot lead the field from the #2 Audi by .8 of a second as a battle for the lead ensued. The #2 and #9 were joined by the lapped #8 of Sarrazin and the three encounted heavy traffic towards the end of the lap twice in succession. 2.3 seconds covered the top three as the #7 of Wurz closed in.

There was trouble lower down the field as the #80 GTE Pro Flying Lizard encountered problems and slowed dramatically before coming into the pits. The #81 GTE Am Flying Lizard of Pumpelly the pulled off with what seemed a terminal problem.

Sarrazin then over took Treluyer to reclaim a lap as his team-mate Wurz closed. The pair then spectacularly over the #70 car in a move reminiscent of that between Hakkinen /Zonta/Schumacher at Spa many years ago, with Treluyer having to take evasive action to avoid incident.

Blue flags then caused the #8 car of Sarrazin to let the #2 Audi repass before he caught and passed the #9 Peugeot for the lead. The pair then pitted on the same lap, however the #2 Audi had pulled a gap between the two.

A 1 minute stop/go for the #8 Peugeot of Sarrazin for a pit stop infringement left his well out of contention, as the hour ended with the good news than the #80 Flying Lizard car was fully fixed after a broken injector wire to the cylinder.

2011 24 Hours of Le Mans standings after eighteen hours

LMP1
No.2 – Audi Sport Team Joest – Fassler/Lotterer/Treluyer
No.9 –  Sport Total – Bourdais/Lamy/Pagenaud
No.7 – Peugeot Sport Total – Davidson/Gene/Wurz

LMP2
No.41 – Greaves Motorsport – Ojjeh/Kimber-Smith/Lombard
No.26 – Signatech – Mailleux/Ordonez/Ayari
No.33 – Level 5 Motorsport – Tucker/Bouchut/Barbosa

GTEPro
No.51 – AF Corse SRL – Fisichella/Bruni/Vilander
No.73 – Corvette Racing – Beretta/Milner/Garcia
No.55 – BMW Motorsport – Farfus/Muller/Werner

GTEAm
No.50 – Larbre Competition – Bornhauser/Canal/Gardel
No 70 – Larbre Competition – Bourret/Gibon/Belloc
No.83 –  JMB Racing – Rodrigues/Menahem/Marroc