It was a one-two for the German carmaker, with the Lucas di Grassi/Marc Gené/Tom Kristensen car finishing second.
Audi said the decision to stick with the R18 was only made “in the final phase”, and that the 2014 race was one of the toughest yet.
“We’ve seen many exciting races and celebrated great victories at Le Mans but this success has a very special significance,” Audi’s Professor Rupert Stadler said.
“We didn’t enter this race as favourites and in Porsche and Toyota had two very strong rivals. That we managed to win Le Mans again this time in spite of this is a fantastic achievement by the whole Audi squad. We’re tremendously happy and my thanks go to all who have made this success possible.”
While Audi stuck with the tried and true diesel-hybrid combination, the team adopted laser headlights on its race-craft for the first time this year.
The victory wasn’t without incident for Audi, with the team forced to change a turbocharger on the leading R18 which saw the car temporarily drop to third place.
The Toyota team put its TS 040 Hybrid on pole and led for much of the first half of the race, enjoying a one-lap advantage over the field at one stage, but electrical problems eventually saw the lead car grind to a halt.
Mark Webber’s Porsche team stayed in the hunt for almost the entire race distance, taking the lead with four hours to go. But two hours later, the 919 Hybrid joined the growing list of retirees due to mechanical problems.
This left the race-winning Audi R18 in front with less than two hours to go, and with a second Audi playing the role of backup in second place (three laps behind), the team just needed to reach the finish. Toyota came away with a podium finish with third place for the Davidson-Lapierre-Buemi entry.
One of the star attractions for this year’s Le Mans 24-Hour - the Nissan ZEOD RC – could only manage five laps before succumbing to drive train issues, but not before the team achieved its goal of completing a full lap under electric power only.
Provisional dates for the 2015 Le Mans 24-Hour have been set as June 13 and 14.
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