The 1-2 result wasn't enough, however, for Acura to wrestle the LMP2 manufacturer championship away from Porsche, as the German marque took the title by just a single point, thanks to a third-place finish for two-time champions Timo Bernhard and Romain Dumas. The Penske Racing duo headed team-mates Ryan Briscoe and Helio Castroneves and the two Dyson Porsches across the line, after overall and LMP2 polesitter Patron Highcroft Racing ran into mechanical problems and the similar Lowe's Fernandez Racing Acura faded to an eventual ninth. The third Penske Porsche completed the top ten ahead of Corsa's LMP1 entry.

Corvette Racing's Olivier Beretta and Oliver Gavin successfully defended their GT1 victory from last season with a comfortable 12.858secs win over team-mates Johnny O'Connell and Jan Magnussen. It was the third win of the season for the Beretta/Gavin duo, who ceded their class championship to O'Connell and Magnussen.

As with the prototype classes, track temperatures some 30 degrees cooler than during practice and qualifying made tyre management critical for the GT entries, and the GT1 class, like the overall result, was decided on one of the many restarts as, after the eleventh yellow flag, Beretta passed O'Connell on the front straight to take the lead with 45 minutes remaining, becoming the first driver in ALMS history to reach 40 career wins, which now include five at Laguna Seca.

"With all the victories I have, I was lucky to drive for a good team and to have very good team-mates," Beretta admitted, "I was not alone. I didn't want to lose today. I knew this was the last chance [to win in 2008], and I was thinking about the restart on cold tyres and driving like I was in the wet. I put the power down and everything went okay. I could have spun because I put the power down very early, but the car stayed on the track and I managed to overtake Johnny."

Tafel Racing closed out the GT2 season with victory for Dirk Muller and Dominik Farnbacher, the Ferrari F430 GT pairing winning for the fourth time as they beat the similarly-mounted Risi Competizione tandem of Jaime Melo and Mika Salo by 5.648secs.

The result was enough to confirm Muller and Farnbacher as second in the class championship behind Flying Lizard Motorsports' Jörg Bergmeister and Wolf Henzler, but was not enough to help Ferrari overcome Porsche's comfortable 15-point lead in the manufacturers' championship.

Although the Prancing Horse swept the top two places at Laguna, fourth place - behind the Milner/Hand Panoz Esperante - for Flying Lizard Motorsports' Patrick Pilet and Johannes van Overbeek was enough to seal the title 220 – 215.

Dirk Werner and Bryce Miller had originally been classified third on the road in the Farnbacher Loles Racing Porsche 911 GT3 RSR, but the car was excluded at post-race tech for a ride height violation due to a broken right front spring.