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
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.