The 2008 24 Hours of Le Mans was the 76th Grand Prix of Endurance, taking place on 14–15 June 2008 at the Circuit de la Sarthe, Le Mans, France, organised by the Automobile Club de l'Ouest (ACO). The test day was on June 1. The race was attended by 258,000 spectators. The Audi team's progress and victory was documented in the 2008 film Truth in 24.

Rule changes On 20 December 2007, the ACO confirmed the previously announced rule changes for the 2008 race and 2008 Le Mans Series season. Petrol engined Le Mans Prototype cars received a 3% larger air restrictor to increase power output and to balance performance between petrol and diesel engines. The performance difference between the LMP1 and LMP2 classes will be increased by decreasing LMP1 class' minimum weight 900 kg, the LMP2 class' minimum weight increased to 825 kg, and a reduction in the fuel capacity of LMP2 cars from 90 litres to 80 litres.

The ACO also added rules regarding the types of engines and fuels which can be used. Production engines which meet the GT1 and GT2 class regulations can now be installed in LMP1 and LMP2 class cars respectively. The use of biofuels will also be allowed in the prototype categories, with petrol engines allowed to run 10% ethanol, and diesel teams allowed to use biodiesel. The GT1 and GT2 categories remained unchanged in the new rules.

Prior to the Le Mans Test Day, Audi announced that they would be the first team to adapt their cars to use 10% biodiesel as allowed by the new rules, with partner Shell developing a biomass to liquid fuel.

Entries

Automatic invitations Automatic entry to the 2008 24 Hours of Le Mans was granted to teams that had performed well in the previous year's 24 Hours of Le Mans, as well as the 2007 seasons of the American Le Mans Series, Le Mans Series, FIA GT Championship, and the Petit Le Mans. The official list of automatic invites was published by the ACO on 16 November 2007, with confirmation of entries accepted by teams published on 18 January 2008.

List of automatic invitations Team Reason Entered Note LMP1 Audi Sport North America 1st in 2007 24 Hours of Le Mans Team Peugeot Total 2nd in 2007 24 Hours of Le Mans Team Peugeot Total 1st in 2007 Le Mans Series championship Pescarolo Sport 2nd in 2007 Le Mans Series championship Audi Sport North America 1st in 2007 Petit Le Mans Autocon Motorsports 2nd in 2007 American Le Mans Series championship1 LMP2 Binnie Motorsports 1st in 2007 24 Hours of Le Mans Entry not taken Barazi-Epsilon 2nd in 2007 24 Hours of Le Mans Ray Mallock Ltd. 1st in 2007 Le Mans Series championship Quifel ASM Team 2nd in 2007 Le Mans Series championship Penske Racing 1st in 2007 Petit Le Mans Entry not taken Penske Racing 1st in 2007 American Le Mans Series championship Entry not taken GT1 Aston Martin Racing 1st in 2007 24 Hours of Le Mans Corvette Racing 2nd in 2007 24 Hours of Le Mans Team Oreca 1st in 2007 Le Mans Series championship Entry not taken Luc Alphand Aventures 2nd in 2007 Le Mans Series championship Corvette Racing 1st in 2007 Petit Le Mans None 2nd in 2007 American Le Mans Series championship2 Vitaphone Racing 1st in 2007 FIA GT Championship Entry not taken3 Scuderia Playteam Sarafree 2nd in 2007 FIA GT Championship Entry not taken GT2 IMSA Performance Matmut 1st in 2007 24 Hours of Le Mans Risi Competizione 2nd in 2007 24 Hours of Le Mans Virgo Motorsport 1st in 2007 Le Mans Series championship Team Felbermayr-Proton 2nd in 2007 Le Mans Series championship Flying Lizard Motorsports 1st in 2007 Petit Le Mans Risi Competizione 1st in 2007 American Le Mans Series championship Motorola AF Corse 1st in 2007 FIA GT Championship BMS Scuderia Italia 2nd in 2007 FIA GT Championship

1. Due to Audi Sport North America already earning two entries, their third automatic entry was passed to the next team in the championship.

2. Due to Corvette Racing already earning two entries, their third automatic entry would have been passed to the next team in the championship. However, no team had run enough ALMS races to be counted towards the GT1 championship, leaving the invitation unassigned.

3. Vitaphone Racing initially turned down their automatic invitation due to their Maserati MC12 not complying with ACO rules. The team however reapplied for a legal Aston Martin DBR9 in the same class at a later date.

Official entry list On 19 February, the ACO published their full list of fifty-five entries plus eight reserves, chosen from a total of 88 applications. The fifty-five main entries were required to appear at the Le Mans test day in order to compete.

Reserve entries Eight cars were granted reserve entries. If any selected team from the main entry list withdrew, a reserve entry would take their place. On April 10, the #81 Tafel Racing Ferrari withdrew and was replaced by the #4 Saulnier Pescarolo-Judd. Although several teams withdrew their reserve entries, none of the remaining reserve entries were promoted to the primary entry list. On Tuesday, June 10, Racing Box's Lucchini-Judd failed official scrutineering and was withdrawn. The first remaining reserve, Epsilon Euskadi's second entry, was allowed to take its place at the start of Wednesday qualifying.

Test session

Drivers, team, and equipment for fifty-five cars arrived at the Circuit de la Sarthe on June 1 to participate in a mandatory test session. Drivers who had not been to the circuit in the past three runnings of the 24 Hours, or had never participated before, were required to complete ten laps of the circuit during the session, while other drivers were allowed to concentrate on setting their cars up for the race two weeks away. Two sessions were held running four hours each, with an hour break for lunch.

Rain dominated the weather during the two sessions, with the track drying out only for brief periods of time before heavy rains dampened the circuit once more. Stéphane Sarrazin, in the #8 Peugeot, was able to set the fastest lap during a brief dry period in the second session, recording a time of 3:22.222. By the end of the test day, Sarrazin's time remained unbeaten, and was in fact nearly four and a half seconds ahead of the second fastest lap, set by the #9 Peugeot. Several hundredths of a second slower still was the #1 Audi, third fastest overall. The fastest car not running a diesel engine was the #17 Pescarolo, recording a time of 3:33.939, over eleven seconds behind the overall leader. In the LMP2 class, the five cars set lap times within three seconds of one another, the Van Merksteijn Motorsport Porsche setting a 3:42.191 lap time to lead the class and place fourteenth overall in the standings. The other Porsche RS Spyder of Team Essex was second fastest, followed by the Barazi-Epsilon Zytek in third.

The Grand Touring categories were led by the previous year's winner in GT1 class, the factory Aston Martin squad. The #009 DBR9 set a lap time of 3:53.531, fast enough for 25th place overall. Larbre Compétition's Saleen set the second fastest lap in the class, nearly two seconds behind. The two factory Corvettes were third and fourth, with the #64 team a few tenths faster than the #63. For the GT2 class, American teams lead the session. Risi Competizione's #82 Ferrari set a 4:05.561 lap time, only three one thousandths of a second ahead of the Flying Lizard Porsche. BMS Scuderia Italia's Ferrari completed the top three in the class, a second slower than the top two.

During the eight hours of testing, practice had to be halted four times for accidents around the circuit. During the first session, the JMB Ferrari spun and hit a wall at Arnage, requiring it to be towed from the track. The Ferrari did however return to the track several hours later after repairs. Shortly after the beginning of the second test session, the Risi-Krohn Ferrari also had a spin, impacting the wall at the Ford Chicane, leading to driver Tracy Krohn being briefly hospitalized. Less than an hour later, Marc Gené in the #7 Peugeot spun in the Karting curve and his 908 became airborne, impacting the wall heavily. Gené was hospitalized with an injured toe, and the car had to be replaced by a new chassis. The final stoppage of practice occurred in the final hour when Joey Foster impacting the wall at the Dunlop Chicane with his Embassy-Zytek.

Qualifying Qualifying was held on 11–12 June, with two individual two-hour sessions being held each day. The first sessions were held at early dusk, while following an hour break, the second sessions ran into the darkness of night. All drivers were once again required to set a minimum of laps to prepare themselves for the circuit; three laps required in the first session, and another three laps in the night session. The best lap time from all four combined determined the starting grid.

Wednesday Following a wet test day, qualifying began under dry conditions. The Peugeot lapped under 3:20 min, lap times reminding of that of the Porsche 917 records set in 1971, when the track had almost no chicanes, and was 120m shorter. Stéphane Sarrazin on Peugeot Nr 8 grabbed pole-position in 3:18.513, shortly followed by Franck Montagny on Peugeot Nr 9 with 3:18.862.

Thursday The second day of qualifying will determine the final grid.

Qualifying times Class leaders and the fastest lap time in each class on each day are in bold. The fastest lap for each car is in gray.